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Synonyms: Calf scour, white diarrhea, septicaemia of calves

Colibacillosis is one of the important diseases in new born calves, piglets, lambs and foals caused by E. coli and characterized by marked postration, profuse diarrhea and septicaemia.

Etiology: Colibacillosis is associated with pathogenic serotypes of E. coli. Certain serotypes cause diarrhea and others cause septicaemia.

(a)  Enterotoxigenic E. coli: is the most common enteropathogen that causes diarrhea in new born farm animals. It causes bacteria by adhering to, colonizing and producing enterotoxins in the small intestine. They are not invasive. The enterotoxins produced by E. coli are of two types: heat stable (ST) and heat labile (LT).

(b)  Enteropathogenic E. coli: they attach tightly to the epithelial cells of the villus of small intestine. They do not produce toxins and seldom invade the intestine.

(c)  Enterohaemorrhagic E. coli: They are Shiga toxin or verotoxin producing strains of E. coli. They are not an important cause of diarrhea in farm animals but some produce diarrhea in calves. E. coli O157:H7, one of the important enterohaemorrhagic E. coli strains cause a broad range of clinical disease in humans including diarrhea in humans and haemorrhagic colitis and highly fatal haemolytic-uremic syndrome in children. 195

Brucellosis, one of the most ancient diseases, continues to be a problem for humans and animals throughout the world causing enormous economic losses and significant human morbidity in endemic areas. The bacterial pathogen is classified by the CDC as a category B pathogen that has the potential for development as a bioweapon. It is one of the important zoonotic disease and considered as the most common laboratory acquired pathogen with >5 lakh human cases reported annually around the world. Brucellosis is a chronic infection which can result in infertility, delayed heat, interrupted lactation, loss of calves, wool, meat and milk production in animals and undulant fever in humans. Although in most of the counties, brucellosis is a nationally notifiable disease and reportable to the local health authority, it is underreported and official numbers constitute only a fraction of true incidence of the disease. Although the true incidence of human brucellosis is unknown, the estimated burden of the disease varies widely from <0.03 to >160 per 1 lakh population. Although only 17 countries in the world are free from the disease, it has been reported in many countries including India. Bovine brucellosis is endemic in all the states in India and appears to be on the increase in recent time, perhaps due to increased trade and rapid movement of livestock. The preponderance of natural bull service in rural India is perhaps yet another important factor in the maintenance and spread of infection. The Government of India has made it mandatory to regularly screen all the breeding bulls from artificial insemination centres, for brucellosis and to use brucellosis free bulls for semen production.

Etiology: Brucella sp. are facultative intracellular Gram - ve coccobacilli, nonspore forming and non-capsulated. It infects macrophages with principal involvement of liver, spleen and bone marrow. Nine Brucella species are currently recognized, seven of them that affect terrestrial animals are: B. abortus, B. melitensis, B. suis, B. ovis, B. canis, B. neotomae and B. microti and two that affect marine mammals are B. ceti and B. pinnipedialis. The first three species are called classical Brucella and within these species seven biovars are recognized for B. abortus, three for B. melitensis and five for B. suis. The remaining species have not been differentiated into biovars.

Synonyms: Pearl's disease, scrofula

It is a chronic insidious contagious disease of man and animals caused by tubercle bacilli characterized by development of tubercles in lung tissue, lymph nodes or other organs resulting in caseation and calcification. The tubercles are frequently located in lungs and lymph nodes. But they may be formed in the liver, spleen, intestine, peritoneum, meninges and long bones. It is a zoonotic disease. Bovine tuberculosis, caused by Mycobacterium bovis (M. bovis) is considered as the serious epizootics of animals and humans. Bovine species are natural hosts to the disease, but a wide spectrum of domestic and wild animals, as well as man, can be infected. Animals reported as having been infected with M. bovis include North American bison (Bison bison), buffaloes (Syncerus caffer), elk (Cervus elaphus), domestic and wild pigs domestic (Sus scrofa), goats (Capra hircus), camels (Camelus bactrianus), dogs (Canis familiaris), cats (Fells catus), sheep (Ovis aries), possums (Trichosurus vulpecula), badgers (Meles meles), mink (Lutreola vison), ferrets (Putorius furo) and non-human primates. All species are not equally susceptible, and are often grouped into spill-over (end) hosts and maintenance hosts. Cattle and other bovine species are considered the primary and most well-known reservoirs or maintenance hosts. In countries where maintenance hosts are present endemically in the wild, infection from these populations to domestic cattle or other farm animals is difficult to avoid. In Africa, bovine TB primarily affects cattle; however, infection in other farm and domestic animals, such as sheep, goats, pigs, dogs and cats, is not uncommon. Wild ruminants and carnivores are also affected and are the natural reservoirs of the infectious agent in the wild. Man is also susceptible to the disease, the highest risk groups being individuals with concomitant HIV/AIDS infection. In Africa, human TB is widely known to be caused by M. tuberculosis; however, an unknown proportion of cases are due to M. bovis. This infection in humans is underreported as a result of the diagnostic limitations of many laboratories in distinguishing M. bovis from M. tuberculosis. TB is a neglected public health problem and accounts for about 25% of all avoidable adult deaths in developing countries. It is of socio-economic significance, as it can affect international trade in animals and animal products. Many factors account for the failure of developing countries to control and eradicate bovine TB, many of them politico-economic. Added to the high costs of a sustainable testing programme are problems of social unrest due to political instability and ethnic wars, resulting in the displacement of large numbers of human and animal populations; lack of veterinary expertise and communication networks; insufficient collaboration with bordering countries and hence a lack of quarantine; and smuggling of live animals across state boundaries. Scarce human and financial resources are often absorbed by action against the high incidence of other acute and fatal diseases, such as contagious bovine pleuropneumonia, foot and mouth disease, African and classical swine fever and parasitic diseases. The primary sources of infection for humans are consumption of unpasteurised milk and close association between humans and animals. Rural inhabitants and some urban dwellers in Africa still consume unpasteurised and soured milk potentially infected with M. bovis. Milk borne infection is the main cause of non-pulmonary TB in areas where bovine TB is common and uncontrolled.

Synonyms: Splenic fever, wool sorter's disease, Tarka

It is an infectious disease of livestock and worldwide in distribution. This is a zoonotic disease. It is also known as splenic fever because of enlargement of the spleen (splenomegaly).

Etiology: It is caused by a rod shaped bacteria of 4-8 µm X 1-1.2 µm known as Bacillus anthracis. It is non-motile, capsulated, aerobic, spore bearing and Gm+ in nature. The organisms remain in chains. It was the first pathogenic bacterium to be observed under the microscope, the first communicable disease to be transmitted by inoculation of infected blood, the first bacillus to be isolated in pure culture and shown to possess spores and the first bacterium used for preparation of an attenuated vaccine.

The capsule is polypeptide in nature being composed of a polymer of d(-) glutamic acid. Capsules are not formed under ordinary conditions of culture but only if the media contain added bicarbonate or are incubated under 10-25% CO₂. Capsules are formed in the body of an infected animal.

Spores are formed in culture or in the soil, but never in the animal body during life. Spores are formed only in the presence of O₂. Spores are central, elliptical or oval in shape. The spores are very resistant to physical and chemical agents. They have been isolated from naturally infected soil for as long as 60 years. They resist dry heat at 140°C for 1-3 h and boiling for 10 min.

Anthrax bacilli is Gm + and non-acid fast. When blood films containing anthrax bacilli are stained with polychrome methylene blue for a few seconds and examined under the microscope, an amorphous purplish material (capsule) is noticed around the bacilli called M'Fadyean's reaction. On agar places, irregularly round colonies are formed 2-3 mm in diameter raised, dull opaque, grayish white with a frosted glass appearance. Under the low power microscope, the edge of the colony is composed of long, interlacing chain of bacilli, resembling locks of matted hair. This is called "Medusa head appearance." Virulent capsulated strains form rough colonies while avirulent or attenuated strains form smooth colonies. On gelatin stab culture, a characteristic 'inverted fir tree' appearance is seen with slow liquefaction commencing from the top.

Crimean Congo hemorrhagic fever (CCHF) was first reported in the 12^th century as a hemorrhagic syndrome in present day Tajikistan. However, in the modern era, the first outbreak of the CCHF was reported in 1944-1945 in the Crimea region with more than 200 cases and the disease was called Crimean Hemorrhagic Fever. Ten years later in 1956, the virus was isolated from a febrile patient in Belgian Congo and this isolate was noted to have the same antigenic structure with the Crimean strains. For this reason, the virus was called Crimean Congo Hemorrhagic Fever. Nowadays, outbreaks of CCHF have been documented in Africa, the Middle East, Eastern Europe, and Western Asia including India. CCHF is a severe hemorrhagic fever with a case fatality rate of up to 50%.

Etiology: It is a tick-borne viral disease belonging to the family Bunyaviridae, genus Nairovirus. Like other Nairoviruses, CCHF virus is an enveloped single stranded negative-sense RNA virus and its tripartite genome consists of a small (S), a medium (M) and large (L) segment which encode for the nucleocapsid protein (NP), the envelope glycoproteins G1 and G2 and an RNA-dependent polymerase, respectively. The virus is transmitted to humans through the bite of infected ticks or by direct contact with viremic animals or humans. Infected humans can spread the disease via close contacts which may result in community outbreaks and nosocomial infections. It is an important human pathogen and could be used as a bioterrorism agent.

Pathogenesis: The pathogenesis of CCHF is not well understood. A common pathogenic feature of hemorrhagic fever viruses is their ability to disable the host immune response by attacking and manipulating the cells that initiate the antiviral response. This damage is characterized by marked replication of the virus together with dysregulation of the vascular system and lymphoid organs. Endothelial damage contributes to hemostatic failure by stimulating platelet aggregation and degranulation, with consequent activation of the intrinsic coagulation cascade. DIC is noted as an early and prominent feature of the disease process. In another study, the levels of interleukin IL-1, IL-6, and TNF-alpha were higher among patients who subsequently died as compared to survivors. The DIC score was higher among fatal cases, correlating positively with IL-6 and TNF alpha levels, and negatively with IL-10 levels. These findings demonstrate that proinflammatory cytokines play a major role in pathogenesis and mortality of patients with CCHF.

Marburg virus (MV) disease was named after the West German town where the largest outbreaks of human infection was reported. It is also known as Vervet monkey or green monkey disease as monkey species introduced the disease in Europe. Marburg disease virus was reported in 1967 in Frankfurt-on-Main and Marburg, West Germany and Belgrade, Serbia in vaccine factory workers who came in contact with blood, organs or cell cultures of African green monkeys. Ebola and Marburg hemorrhagic fevers are severe zoonotic diseases seen not only in humans but also in non-human primates. Most species of Ebolavirus and the only known species of Marburg virus occur in Africa. Primates are infected sporadically from an unknown source probably bats. Humans seem to become infected directly from bats in caves, as well as when they, come in contact with tissues from infected apes and other species. Once the virus has entered the population, it can spread from person to person. Some epidemics affect hundreds of people. Although the mortality rate varies, 90% case fatalities have been reported in the most pathogenic viruses. No vaccine is available and the only treatment is supportive. Epizootics in gorillas and chimpanzees are equally serious, and appear to threaten the survival of these species in the wild. Other wild mammals including duikers also seem to be killed during outbreaks. One species of Ebolavirus, Reston Ebolavirus, occurs in the Philippines. Until 2008, this virus was known only as an infection of nonhuman primates. It does not appear to be a human pathogen; although some people in contact with this virus have seroconverted, they remained asymptomatic. In December 2008, Reston ebolavirus was discovered in pigs during an unusually severe outbreak of porcine reproductive and respiratory syndrome (PRRS) in the Philippines.

Etiology: Ebola and Marburg hemorrhagic fever are caused by members of the genera Ebolavirus and Marburgvirus, respectively. These viruses are the only members of the family Filoviridae. The genus Ebolavirus contains four recognized species: Zaire ebolavirus (formerly Zaire Ebola virus), Sudan ebolavirus (formerly Sudan Ebola virus), Ivory Coast ebolavirus (formerly Cote d'Ivoire Ebola virus) and Reston ebolavirus (formerly Reston Ebola virus). At least 13 strains of these viruses have been identified. A fifth species, tentatively named Bundibugyo ebolavirus, was isolated from a recent outbreak in Uganda. Marburg virus contains a single species, Lake Victoria Marburgvirus (formerly Marburg virus). Six strains of Lake Victoria Marburgvirus had been recognized as of 1990; at least nine genetically distinct strains were identified from a more recent outbreak in the Democratic Republic of the Congo. Marburg virus contains ssRNA as genome. The virion is highly pleomorphic and measures 80 nm in diameter and 700-1000 nm in length. Filoviruses can be destroyed by autoclaving. Treatment with sodium hypochlorite (1:100 dilution of household bleach) or standard hospital disinfectants can also be used. Ebolaviruses are reported to be susceptible to 2% sodium hypochlorite, 2% glutaraldehyde, 5% peracetic acid and 1% formalin. These viruses can also be inactivated by ultraviolet light, gamma irradiation, 0.3% betapropiolactone for 30 minutes at 37°C (98.6°F), or heating to 60°C (140°F) for 1 hour. Marburgvirus is susceptible to 1% sodium hypochlorite, 2% glutaraldehyde or formaldehyde, ultraviolet light and heat.

Hantaviruses have been responsible for a variety of human illnesses particularly haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). There are currently 47 recognized sero/genotypes of hantaviruses with considerable geographic diversity. Each hantavirus type appears to be specific to a different rodent host. The different hantavirus types are associated with different types of disease both in terms of target organs and disease severity. HFRS is primarily a disease of the Old World while HPS is a disease of New World. Although the disease may have first been recognized as early as 1000 years ago in China, it affected >3000 United Nations Soldiers during Korean war (1950-1953). Now it is reported that hantavirus affect as many as 2 lakhs people each year in Asia and Europe. The agent of this virus remained unknown until 1978 when Lee and his associates isolated and named Hantaan virus, after a river in South Korea. Other viruses antigenically related to Hantaan virus were characterized and placed under the genus Hantavirus and family Bunyaviridae.

Over the past few decades, the sharp increase of incidences of hantavirus disease in humans throughout the world has been reported. There are 47 recognized hantaviruses with considerable geographic diversity. But the number of hantavirus virus types recognized continues to grow. Hantaviruses cause persistent infections in rodent reservoirs which directly impact transmission of these zoonotic agents between rodents and from rodents to humans. Environmental, 127 demographic and physiological factors likely interact to mediate responses to hantaviruses in natural rodent populations. Although not much work has been carried out, comparisons of human and rodent immune responses to hantaviruses may provide insights into why hantaviruses often are fatal for humans but cause only persistent infections in rodents.

Nipah virus infection is an emerging zoonotic disease first described in 1999 and the virus is under the genus Henipavirus and family Paramyxoviridae. The disease is similar to another emerging zoonotic disease caused by Hendra virus and can spread from its wildlife reservoir to pigs and humans where it causes an often fatal disease. It is a notifiable disease in most countries and to be handled under highest biological security level 4 (BSL-4). In Malayasia an outbreak of viral encephalitis occurred over a 35 week period from September 29, 1998 to 31^st May, 1999 among pig farmers creating considerable anxiety and fear. Of the 265 cases reported to the Ministry of Health in Malaysia, 105 were fatal and the case fatality rate was 39.6%. The outbreak also spread to neighbouring Singapore where 11 workers of an abattoir developed the disease with one fatality. 93% of the reported cases involved those directly in the pig farming industries namely pig farm workers, pig farm proprietors, housewives and family members assisting in the farms. The majority of the cases occurred in those aged 20 and above (92.4%) and actively engaged in pig industry followed by the age group 10-19 years (6.4%). About 82.6% of the cases are male.

Etiology: Henipavirus is a genus of the family Paramyxoviridae and order Mononegavirales containing two members, Hendravirus and Nipah virus. The henipaviruses are naturally harboured by Pteropid fruit bats (flying foxes) and are characterized by a large genome (18.2 Kb), wide host range and their recent emergence as zoonotic pathogens capable of causing illness and death in domestic animals and humans.

The viruses are pleomorphic ranging in size from 40-600 nm in diameter. They possess a lipid membrane overlying a shell of viral matrix protein. At the core is a single helical strand of genomic RNA tightly bound to N (nucleocapsid) protein and associated with the L (large) and P (phospoprotein) proteins which provides the RNA polymerase activity. F (fusion) protein trimers and G (attachment) protein tetramers are embedded within the lipid membrane. The genome of the Nipah virus consists of a non-segmented, single stranded negative sense RNA. In common with other members of the Paramyxovirinae subfamily, the number of nucleotides in the Henipavirus genome is a multiple of six, known as the 'rule of six'. The Nipah virus has been classified by the CDC as a Category C agent.

Hendra, a disease of horse has been recognized in Australia since 1994-95 with zoonotic importance. It is caused by a virus under the genus Megamyxovirus and subfamily Paramyxovirinae and family Paramyxoviridae. This virus is also endemic in certain species of bat. Another zoonotic bat virus called Nipah virus has been placed under the same genus and family. It is transmitted between the horses through contact. Infected horses can develop a severe and fatal respiratory disease characterized by dyspnoea, vascular endothelial damage, pulmonary oedema and neurological signs. Experimental infection of cats and guinea pigs showed fatal respiratory disease. The transmission of virus from horse to horse and horse to man is through close contact. One person died of the disease due to respiratory failure and another one due to delayed onset of encephalitis. A number of diagnostic methods are available to provide prompt, sensitive and accurate diagnosis of the disease.

History: In 1994-95, a new viral zoonotic disease was identified in Queensland, Australia resulting in death of 2 human and 15 horses in two separate incidents. Again, in 1999 another horse died at the same place. The term 'Hendra' has been derived from the name of a place, suburb of Brisbane where first outbreak took place. In September 1994, a total of 15 horses died due to hyperacute respiratory disease. The trainer of the horse also died. In 1995, a farmer died of meningoencephalitis after having contact with a Hendra positive horse. In the 1999, a mare died of Hendra virus infections.

Etiology: The Hendra virus is under the new genus Megamyxovirus and family Paramyxoviridae. The Hendra virus was isolated in Vero cells from lung specimens and produced CPE within 3 days. The virus can grow in MDCK, BHK, RK13, LLC-MK2 and MRC5 cells. It also grows in cells derived from birds, reptiles, amphibians, fish and in embryonated chicken eggs. The virus does not have haemagglutinin or neuraminidase activity. The virus is pleomorphic in shape, 38-600 nm in diameter and enveloped with two glycosylated transmembrane proteins of different lengths (15 and 18 nm). It differs from respirovirus and rubulavirus in not using sialic acid containing receptors. The virions are labile and infectivity is destroyed by heat, lipid solvents, non-ionic detergents, formaldehyde and oxidizing agents. Virions contain one molecule of negative sense ssRNA about 15 Kb long which codes 8 proteins. The Hendra virus is the largest of all known viruses under Paramyxoviridae. The genetic studies showed that Hendra virus is more similar to Morbillivirus or intermediate between Morbillivirus and Respirovirus. The amino acid homology between Hendravirus and Morbillivirus varies from 17-21% (P protein) to 40-42% (M protein) compared to 6-10% and 8% respectively for other members of Paramyxoviridae. A new Hendra like virus has been identified as a cause of respiratory and neurological disease in pigs and humans in Malaysia, called Nipah virus, after a village where the first human case occurred. (The amino acid homology of N protein between Hendra and Nipah is 92%, whereas in case of P&V it is 80-85%). Like, Hendra virus, the Nipah virus is thought to have emerged from a fruit bat (Pteropus hypomelanus).

This is an acute viral encephalitis having public health importance. It is under the genus Flavivirus and family Flaviviridae. The genus Flavivirus comprises of group of arbovirus though a few members of the genus have no known vector. The genus contains over 70 viruses of which 40 are mosquito borne, 16 are tick borne and 18 have no known vector. The type species of the genus is yellow fever virus. Although all flaviviruses are serologically relate, they can also be grouped serologically into distinct groups: dengue serological group, the JE serological group and a less serologically cohesive yellow fever virus group. The disease has been recognized in Japan since 1871 and was named Japanese B encephalitis to distinguish it from 'encephalitis A' (encephalitis lethargica, Von economo's disease) which was then prevalent. The virus was first isolated in Japan during an epidemic in 1935.

Etiology: JE virus is under the genus Flavivirus and family Flaviviridae. The genome is about 11 kb which encodes 3 structural proteins (C, capsid protein, PrM the membrane precursor protein that is cleaved proteolytically by a cellular protease to form the M protein in mature virions, and E, envelope protein) and 7 non-structural (NS) protein (NS1, NS2a, NS2b, NS3, NS4a, NS4b, NS5). The Eglycoprotein is the most immunologically important protein. The Japanese encephalitis serological group of flaviviruses comprises eight virus species and two subtype viruses with a geographic range encompassing all continents except Antarctica. The major virus species and their geographic range are as follows: the Japanese encephalitis virus ( JEV) in eastern, southern and southeastern Asia, Papua New Guinea and the Torres Strait of northern Australia; the West Nile virus (WNV) in Africa, southern and central Europe, India, the Middle East and North America and as Kunjin virus ( a subtype of WNV) in Australia and Papua New Guinea; the Murray Valley encephalitis virus (MVEV) in Australia, Papua New Guinea and the western Indonesian archipelago and the St. Louis encephalitis virus (SLEV) in North and South America. The other minor members of the group are Usutu (USUV), Koutango and Yaounde viruses in Africa; Cacipacore virus in South America and Alfuy, a subtype of MVEV, in Australia.

Chikungunya has been emerged as an important public health problem in the Indian Ocean Islands and India recently. Epidemiological, geographical and demographic data suggested that 1.38 million people were affected by the disease in India in 2006. The actual incidence of the disease may have been higher but underreporting did not reveal the actual picture. A large proportion of those who became ill consulted private health care professional or sought alternative medical care such as Ayurveda or homeopathy not included in the data collected by Govt. officials.

During the epidemic, rural hospitals, private and public clinics flooded with victims of Chikungunya. The virus did not kill its victims but inflicted considerable pain and misery besides local, regional and national financial burden towards health care. Only National Institute of Virology (NIV) and National Institute of Communicable Disease (NICD) provided accurate diagnosis of the disease. The Chikungunya assumed epidemic proportions because viral agent mutated, the vectors discovered the new ways to spread and the host lacked immunity to fight the disease. Modern transport systems - cars, buses, trains and aircraft particularly the movement of humans played a key role in spreading the disease that helped to maintain man-mosquito man cycle.

Etiology: First isolated in Tanzania in 1953, Chikungunya is under genus Alphavirus and family Togaviridae. It contains a single stranded positive sense RNA with a length of 12 Kb coding 4 non-structural (nspl - nsp 4) and 3 structural proteins (E1-E3). Among the structural protein, El protein correlates with serological response in human hosts and also modulates penetration of the virus in the mosquito species. Genetic analyses and historical accounts suggest that the Chikungunya virus originated in tropical Africa and subsequently evolved into 3 distinct genotypes - the East African, the West African and the Asian genotypes. The Asian genotypes have a high degree of nucleic acid sequence homology among themselves but the African strains exhibit wider sequence diversity and have been shown to undergo genetic micro-evolutions even during the course of an epidemic. Prior to the 2006 epidemic in India, the 3 genotypes were restricted to the geographical areas only. Previous outbreaks in India (1963 and 1973) were caused by the Asian genotypes, but the 2005 epidemic in the Indian Ocean Islands and the 2006 epidemic in India have been attributed to the East African genotype which arrived in India 5 years ago.

Dengue is a mosquito-borne viral disease and considered to be a major health problem globally. It is also called break-bone fever, dandy fever, denguero bouquet fever, giraffe fever, Polka fever and 5 days or 7 days fever. There are two important manifestations, namely dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) which are responsible for heavy morbidity and mortality every year causing serious concern to health. It is an important disease caused by an arbovirus worldwide especially in the tropical and subtropical regions. The severity of the disease can be judged from simple statistics that over 40 per cent (2.5 billion) of the world's population in 100 countries continue to live under threat of contracting dengue infection. Annually, dengue virus infections are responsible for up to 100 million cases of dengue fever and more than 500,000 cases of haemorrhagic fever. Besides, every year the disease forces nearly 500,000 people to hospitalization of which 90% are children and causing 24,000 deaths. Mostly these deaths are due to lack of early diagnosis of dengue virus infection. In DHF case fatality rate generally exceeds 20 per cent in a non-endemic population and it can be reduced to less than 1 per cent with the aid of modern supportive therapy based on early diagnosis of the type of viral infection.

Dengue fever (DF) is an acute febrile viral disease characterized by headaches, bone or joint and muscular pains, rash and leucopenia as symptoms. Dengue haemorrhagic fever (DHF) is characterized by four major clinical manifestations: high fever, haemorrhagic phenomena, 73 often with hepatomegaly and in severe cases, signs of circulatory failure. Such patients may develop hypovolaemic shock resulting from plasma leakage. This is called dengue shock syndrome (DSS) and can be fatal.

The year 2001 witnessed unprecedented global dengue epidemic activity in the American hemisphere, the Pacific Islands and continental Asia. During 2002, more than 30 Latin American countries reported over 1 million DF cases with large number of DHF cases. This has been followed by extensive epidemics of DHF in several parts of India during 2003.

Dengue fever (DF) is caused by ingestion of viraemic blood containing dengue virus by mosquitoes of Aedes sp. followed by passage to a second human host. An extrinsic incubation period is required before the virus appears in the saliva of the transmitting female Aedes mosquitoes. After the bite, there is an incubation period of 3 to 14 days (average 4 to 7 days) followed by the onset of fever and nonspecific signs and symptoms (frontal headache, retro-orbital pain, body aches, nausea and vomiting, joint pains, weakness and rash). The febrile phase is self limiting and may last for 2 to 10 days followed by remission of fever in most cases. Laboratory abnormalities include neutropenia followed by a lymphocytosis and thrombocytopenia.

Swine influenza (Swineflu) is a highly contagious viral disease of pigs. It is an upper respiratory tract disease of pigs that causes outbreaks in herds. Swineflu infects people every year and is found typically in people who have been in contact with pigs although there have been person to person transmission of the disease. Influenza A virus subtypes namely H1N1, H1N2 and H3N2 are circulating around the world. In US, H1N1 subtype was exclusively prevalent among swine population before 1998 however since late August 1998, H3N2 subtype has been isolated from pigs. Most of the H3N2 virus isolates are triple assortants containing genes from human (HA, NA and PB1), swine (NS, NP and M) and avian (PB2 and PA) lineages. Influenza viruses are generally species specific i.e. avian influenza virus will infect only birds, swine influenza virus pigs, human influenza virus humans and so on. Although interspecies transmission of influenza viruses are reported, the transmission of influenza virus from one species to another is not always possible. Again, influenza A virus isolated from pigs can acquire the pandemic potential but not isolated from other species. Further, recent outbreaks of swineflu affecting human beings in Mexico, USA, UK,Canada, Asia etc with a death toll of 49 persons resulted in high alert in all the countries and compulsory checking of all the persons coming from the affected countries to other counties. The causative agent of swineflu is H1N1. So, it is the prime time to create awareness about the disease among the public which in turn help in tackling the disease in an effective and efficient manner and to prevent its transmission to human beings from swine species.

Etiology: Swineflu is caused by a virus under the genus Influenza A virus and family Orthomyxoviridae. Influenza A viruses are spherical with a diameter of 80-120 nm and may be filamentous. There are two types of surface glycoproteins namely haemagglutinin (HA) and neuraminidase (NA) present on the virus particles. A total of 17HA and 10NA types have been reported in influenza A viruses. It contains 8 copies single stranded negative sense RNA molecules as genome which encode 12 proteins: 3 subunits of the viral RNA polymerase complex, PB1 (encoding 3 proteins PB1, PB1-F2 and N-40), PB2 and PA; a nucleoprotein (NP), two surface glycoproteins, HA and NA, a matrix protein (M1), an ion channel protein (M2), a nonstructural protein (NS1) and a nuclear export protein (NEP- also known as NS2). There are 170 combinations of two surface glycoproteins, 17 HA and 10 NA that determine the antigenic properties and subtype classification of virus. However, human disease historically has been caused by 3 subtypes of HA (H1, H2 and H3) and two types of N (N1 and N2). Further in 1997, the outbreak of avianflu/birdflu in Hong Kong affected 18 persons with a death of 6 persons. The avian influenza virus responsible for that outbreak was H5N1. From that time H5, H7 and H9 ( all from avian origin) have been implicated in causing disease in human beings.

Avian influenza (AI) is a listed disease of the World Organization for Animal Health (OIE) that has become a disease of great concern for both animal and human health. Avian influenza (AI) or 'bird flu' is an infectious disease of birds ranging from a mild to a severe form of illness. It is caused by influenza A virus under the family Orthomyxoviridae. It is an enveloped virus with two types of surface projections haemagglutinin (H) and neuraminidase (N). The haemagglutinin is a rod shaped homotrimer which agglutinates RBCs and neuraminidase is a mushroom shaped homotetramer which releases the virus from cells because of its sialidase activity. There are 17 different H antigens (H1 to H17) and 10 neuraminidase antigens (N1 to N10). The virus also contains 8 single stranded negative sense RNA segments each of which encodes for a protein. Avian influenza virus is generally limited to poultry but an unprecedented epizootic of avian influenza A (H5N1) that is highly pathogenic has crossed the species barrier in Asia to cause many human fatalities and likely to possess an increasing pandemic threat. Zoonotic potential of AI virus was first recorded in 1997 with hospitalization of 18 people (six died) following the infection with HPAI (H5N1) in Hong Kong. This provided the evidence that HPAI strains of chicken can adapt, multiply and even cause death in affected individuals. So, it is the prime time to create awareness about the HPAI and its transmission to human beings so that necessary precautionary measures can be taken to prevent and control the disease efficiently and effectively.

Etiology: Influenza viruses are under the Orthomyxoviridae family and belong to either influenza A or influenza B or influenza C genus. The virus particles are enveloped with glycoprotein projections having haemagglutinin or neuraminidase activity and contain 8 negative sense single stranded RNA. Influenza A viruses are classified into subtypes based on these two surface antigens, haemagglutinin (H) and neuraminidase (N ). The haemagglutinin is a rod shaped trimer which agglutinates RBCs and neuraminidase is a mushroom shaped tetramer which releases the virus from cells because of its sialidase activity. Beneath the lipid envelope there is a membrane or matrix (M) protein which surrounds a helical complex containing the nucleoprotein (NP) and polymerases (PB1, PB2, P) protein. There are also two nonstructural protein (NS) present in the virus. There are 17 haemagglutinin antigen (H1 to H17) and 10 neuraminidase antigens (N1 to N10) present in influenza A viruses. Each RNA strand of AI virus code for at least one protein. The H glycoprotein of influenza virus has two important functions which are imperative for the infectivity of the virus (i) it is responsible for attachment of the virus to the host cell receptors of glycoprotein or gangliosides containing sialic acid. (ii) it possesses fusion activity between the host cell membrane and the virus membrane so that virus genetic material is introduced into the host cell. The glycoprotein is produced as a precursor, HAo which requires post translational cleavage to HA1 and HA2, by host proteases before it is able to induce membrane fusion. Then only the B virus particles becomes infectious. Type A viruses include the avian, swine, equine and human influenza A viruses. The large number of subtypes present in the type A influenza viruses are due to fact that viruses often undergo antigenic shift by the process of genetic reassortment.

Synonyms: Hydrophobia, Lyssa, Jalatanka

This is an acute highly fatal viral disease of all warm blooded animals including man characterized by signs of abnormal behaviour, nervous symptoms (increased excitability and irritability), impairment of consciousness ascending paralysis and death. The disease was variously known as lytta or lyssa coming from the belief that the disease was caused by a worm under the tongue (lytta) or hydrophobia, which describes the thirst and fear of water associated with the disease. The English name rabies derived from Latin word ‘Rabere’ which has been derived from Sanskrit word ‘Rabhas’ meaning raging, furious, savage, madness or to do violence whereas Greek term hydrophobia is now specifically used for rabies in man. The symptom hydrophobia (fear of water) is developed due to painful spasm of muscles of deglutition.

Distribution: The disease is known since ancient time. The disease has been recorded in various parts of the world in different species of animals. Australia, Britain, Scandinavian, New Zealand, Singapore, Hong Kong, Hawaii and some other Islands are free from rabies. This was possible due to strict quarantine measures and restriction on import of animal and animal products from disease prone areas. Lot of outbreaks are reported in India throughout the year causing 30,000 death annually and number of death toll may be higher as many cases go unnoticed. India accounts for the 80% casualties from rabies worldwide.

1. The Aflatoxin Molecule

Aflatoxins are chemically difuro-coumarin derivatives. Presently, 18 different types of aflatoxins have been identified with aflatoxin B₁, B₂, G₁, G₂, M₁ and M₂ being the most common. Of these Aflatoxin B₁ (AFB₁) and G₁ occur most frequently, with AFB₁ being the most potent. Physicochemical and biochemical characteristics of the AFB₁ molecule reveal two important sites for toxicological activity (Heathcote and Hibbert, 1978). The first site is the double bond in position 8,9 of the furofuran ring (Figure 1). The interactions of aflatoxin, DNA and proteins, which occur at this site alter the normal biochemical functions of these macromolecules and leads to deleterious effects at the cellular level.Monteiro et al. (1966) studied the in vitro interaction of groundnut proteins namely arachin and conarachins with AFB₁ molecule. The second reactive group is the lactone ring in the coumarin moiety (Lee et al., 1981). The lactone ring is easily hydrolyzed and is therefore vulnerable to degradation.

1. Introduction

Foods are complex biologically and chemically active systems that require close monitoring of their manufacturing, distribution and storage conditions in order to maintain their nutritive value, safety and sensory qualities by suitable chemical. The determination of trace impurities in food system presents considerable difficulties owing to complexity as it contains thousands of major and minor compounds (Nilufer and Boyacio, 2002). The choice of the method of analysis depends on the sample, the analyte to be assayed, accuracy, limit of detection, cost and time to complete the analysis (Aboul- Eneim et al., 2000). The chemical methods employed for food analysis and quality control are generally time consuming and require tedious or destructive sample preparation. For development of the new detection method, emphasis should be on development of simplified, cost-effective and efficient procedures that complies with the legislative requirements (Stroka and Anklem, 2002; Enker, 2003).

The molecular spectroscopy is a fast, accurate, easy and non-destructive technique that can be used as a replacement of time-consuming methods. Near infrared (NIR) spectroscopy has proved to be a powerful analytical tool used in the agricultural, nutritional, petrochemical, textile and pharmaceutical industries (McGlone and others, 2002; Esteban-Diez and others, 2004). Infra red spectroscopy is based on the absorption of infra red light by the substance to be measured. This absorption excites molecular vibrations and rotations, which have frequencies that are the same as those in the infrared range of the electromagnetic spectrum (Pande and Mishra, 2015). This application uses a fiber optic coupled FT-NIR system operating in the 10,000 – 4,000 cm^-1 region in reflectance mode. It involves the analysis and quantification of molecular responses to introduced signals of known energy or frequency. All molecules (e.g. water, glucose, protein) have a definite amount of energy. When alternate energy (e.g. infrared radiation) is introduced, an energy exchange occurs between the introduced energy and the energy contained within the molecule. This is expressed as absorbance (energy is absorbed resulting in a loss of introduced energy), attenuated (energy is scattered resulting in a loss of introduced energy) or emitted (energy is released resulting in a gain on the introduced energy). As individual molecules and molecular groups (e.g. alcohols, nucleic acids, proteins, sugars and fats) have definite energy, by applying external energy of a known amount/type, one can structurally identify, quantify and even determine the natural state of these molecules within complex samples and mixtures.

1. Introduction

Product development is a basic activity in the food industry. Each company has a product mix, often including hundreds of products, which are constantly evolving - old products dying, products reaching maturity, products contributing to rapid growth and new products being introduced.

In the food industry, just as any other industry, product and process development is considered a vital part – indeed the lifeblood – of smart business strategy. Failure to develop new and improved products relegates firms to competing solely on price which favours the players with access to the lowest cost inputs (land, labour etc). Product and process development (commonly referred to as product development) is systematic, commercially oriented research to develop products and processes satisfying a known or suspected consumer need. Product development is a method of industrial research in its own right. There are essentially four basic stages in the model product development process.

1. Introduction

India is a land of large varieties of fruits and vegetables due to its vast soil and climatic diversity. India is the second largest producer of fruits and vegetables in the world, with an annual production of fruits 45.5 Million tonnes and vegetables 90.8 Million tonnes. It contributes 10.23% and 14.45% of the total world production of fruits and vegetables (F&V) respectively (NHB, 2010). Though fruits and vegetables are grown only on 7–8% of gross cultivated area, these contribute more than 18.8% of the gross value of agricultural output and 52% export earnings from total agricultural produce. These have a high export potential of 20-30 times more foreign exchange per unit area than cereals due to higher yields and higher price available in the international market (Sen et al., 2012). According to estimates, the per capita consumption of fruits and vegetables in India is only around 46g and 130g which are far below the stipulation of a minimum of 92g and 300g respectively as recommended by the Indian Council of Medical Research and National Institute of Nutrition. The low availability is mainly due to considerably high post-harvest losses. About 15-20% of the fruits and vegetables are wasted every year in the country, due to poor post-harvest management and lack of infrastructural facilities for processing and storage, amounting to a revenue loss of over Rs. 625 billion.

The sensorial, nutritional, and organoleptic quality of fresh produce starts deteriorating after harvest as a result of soon after harvest the altered plant metabolism and microbial growth. The quality deterioration is the result of produce respiration and transpiration, senescence, ripening-associated processes, wound-initiated reactions, development of postharvest disorders, microbial proliferation leading to postharvest quality loss. Therefore, it is necessary to understand the respiration and ripening processes and the physiological and biochemical changes during ripening. The best way to reduce respiratory metabolism is to reduce the storage temperature. All biological processes proceed more slowly at lower temperature (Yahia, 2007). In general, O₂ levels must be reduced to less than 10 % to see a reduction in the rate of respiration. Respiration rate is temperature dependent; so, as the temperature reduces the amount of oxygen required also drops. Therefore, oxygen levels must be substantially reduced at low temperature for it to affect the rate of respiration. It must however, be ensured that O₂ levels do not fall below extinction point as anaerobic respiration and decay may occur. Tolerance to low O₂ varies between species and cultivars and is also time dependent. Commodities may be able to tolerate low O₂ for short periods of time. Low O₂ can also be tolerated when CO₂ is low.

1. Introduction

Antioxidants are considered an important class of nutraceuticals which are associated with health improving properties. Antioxidants are compounds which when present in foods at concentrations lower than an oxidizable substrate, markedly delay or prevent the oxidation of substrate (Halliwell, 1999). They are increasingly applied in food systems to retard the oxidation process, particularly in lipid containing foods (Droge, 2002; Lee et al., 2004). The commercially available solutions to counter food oxidation are predominated by synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tertiary butyl hydroquinone (TBHQ), among others, which are increasingly rejected by consumers and legitimized by regulators due to long term health implications (Park et al., 2001). As a consequence, the development and utilization of natural antioxidants as alternatives to synthetic ones have attracted global interest among researchers.

The use of spices and herbs in foods was known since ancient times to modify or to improve the flavor. However, the antioxidant properties of only some of the spices have been recognized. Different spices and their extracts such as turmeric, ginger, fennel, rosemary, and sage, among others, are reported to possess very high antioxidant properties, owing to the content of biologically active compounds, which enables their food application (Madhavi et al., 1996). Exploitation of natural antioxidants in consumer goods is increasingly accepted and will gain momentum due to the rise of green consumerism. In this chapter, an attempt has been made to provide an insight into natural antioxidants and colors. Beginning with the source distribution of natural antioxidants, followed by review of extraction methods for their isolation from plant based matrices and bio-preservative properties in vegetable oils to delay rancidity. Lastly, a thorough collection of literature pertaining natural colors has been presented to potentiate the application of clean label ingredients in food systems. The application of natural antioxidants and colors in food products can vouch the food safety with value addition in terms of their nutraceutical properties.

1. Introduction

Storage is an important part of any food grain processing chain. Storage of raw and processed food grain has been used by humans since time immemorial as a prerequisite for insuring food security due to off time availability, and for holding seed grain for long periods (Pande and Mishra, 2012). After harvesting grains may be required to be stored for long periods before these are marketed or used as food or seed. The grain storage is mainly carried out for three purposes viz (i) to retain a supply of food (ii) to service a trading system and (iii) to retain seed for planting the following season (Hall, 1980). Storage is, therefore, carried out by the producer, trader, processor, and the exporter and at all these levels the methods adopted affect the quality of food stuffs. The length of time grains can be safely stored will depend on the condition it was harvested and the type of storage facility being utilized. Grain storage and handling is a major concern for food grain growers and processers worldwide (Mohan et al., 2011; Pande and Mishra, 2012). Depending upon the condition and uses food grains may be stored in different storage structures using traditional or modern storage methods. Different storage structures are used by farmers with the traditional names like Gumma, Oliya and Jute bag. Caswell (1973) recorded 50 to 60% of insect damage on food grain after six months of traditional storage. A typical range of storage methods encountered in tropics and subtropics region is given in Table 1.

1. Introduction

Dairy industry size and demand precede all other segments of food industry. Reporting milk production of 146.3 million tonnes in 2014-15, India is currently occupying first position in world scenario (NDDB, 2015). In spite of limited shelf-life, milk offers various opportunities of product diversification, processing optimisation and convenient packaging solutions. All categories of dairy products are unique and vary in market value. The operating margins in value-added dairy products are almost twice of liquid milk business due to reduced need of refrigeration and added shelf-life. The appeal and satiety it offers makes them ambrosia for consumers. Baked and fried dairy products (BFDP) are those class of dairy products in which main processing operation is either baking or frying. In addition to preservation of milk solids for longer time at room temperature, manufacture of baked and fried dairy products add value to milk and also provide considerable employment opportunity (Pal and Raju, 2007;Patil, 2011). The characteristic flavour and colour development of the product rely on this unit operation or cooking method and it cannot be replaced. The unique difference in baked and fried dairy products is that in baking dough is prepared and for frying batter is prepared which vary significantly in characteristics (Table 1). The quality of the finished product greatly depends on how the dough or batter is handled.

The nutritional richness and the high biological value of dairy milk have made it an important constituent of the balanced human diet. It is associated with better growth, improved status of some micronutrients, cognitive performance, motor development and activity. It is composed of a mixture of nutritive components as well as other bioactive factors such as biogenic amines, conjugated linoleic acid (CLA), with relevant physiological benefits. The consumption of dairy milk and products exert a protective action in human health and have been confirmed in preventing several chronic conditions like cardiovascular diseases (CVDs), some forms of cancer, obesity, immunomodulation and diabetes (Pereira, 2014). The chemical composition of bovine milk consists of 87% water, 4% to 5% lactose, 3% protein, 3% to 4% fat, 0.8% minerals, and 0.1% vitamins (Pereira, 2014).

1. Composition of Milk Fat

Bovine milk contains about 3.5 to 5% total lipid, existing as emulsified globules 2 to 4 μm in diameter and coated with a membrane, casein. The composition of milk fat is somewhat complex. Triglycerides constitute approximately 98% of milk fat, which is found in the milk globule, with the remainder being made up of di- and monoglycerides, phospholipids, cerebrosides, cholesterol, vitamins, tocopherols, carotene, and flavor components. Phospholipids are about 0.5 to 1% of total lipids, and sterols are 0.2 to 0.5%. These are mostly located in the milk fat globule membrane (Jensen et al., 1991). Cholesterol is the major sterol at 10 to 20 mg/dL.

1. Introduction

A confection is sweet tasting delicacies developed using sugar and other carbohydrates with optionally selected chocolate, nuts, fruits, vegetables or gums. Depending on the formulation, the confection may vary from sugar boiled hard lozenges to gum based soft gummy toffees, from chewing gums to mouth melting chocolates. The versatile and broad variation in the product created by differentiating flavours, ingredients and processing has greatly influenced the market demand of these products. Although confection is non-essential commodity but still relished by people of all economic strata and hence creating a great market space and scope of new products.

In confectionery research and development area, current popular sector is functional confections. The sector has been on the trends radar globally, accounting for 8% of the global confectionery market, and most accepted and successful in Japan.

1. Introduction

Each day, millions of people take a small bag, drop it into a cup, pour in boiling water, and add a dash of milk plus a spoonful of sugar. People start the day with it, end the day with it, and also serve it socially or in times of distress (Herath and De Silva, 2011). The reason behind its popularity is based on the fact that the combination of theanine amino acid contained in tea and melatonin and B-complex vitamins contained in milk offers superior relaxing effects. Furthermore, the harmony of tea’s sweet aroma and milk’s natural sweetness will create a healthy low calorie drink.

Tea is one of the most pleasant drinks consumed by two third of the world’s population. It is not only the most popular and one of the oldest known beverages in the world but also an antioxidative agent available in everyday life which may help to prevent a wide variety of diseases such as cancers and heart diseases (Yang and Landau, 2000; Luczaj and Skrzydlewska, 2005). Tea provides a significant source of phenolic compounds in the diet. While polyphenols have long been of interest for their contribution to the astringenttaste of teas (Ding et al., 1992), research into the health benefits of tea has been actively pursued only in more recent times (Dufresne and Farnworth, 2001; Yamamoto et al., 1997). Even though the results are mixed for the relationship between tea and health in epidemiological and clinical studies, in vitro studies point to a range of mechanisms by which tea phenolics may help to offset chronic diseases such as cancer and cardiovascular diseases (Kris-Etherton and Keen, 2002).

1. Algal Biomass

Algae is defined as heterogeneous assemblage of organisms that range in size from tiny cells to giant seaweeds, thus algae mostly are photosynthetic species which include eukaryotes and prokaryotic Cyanobacteria (blue-green algae) and live in aquatic habitats. They are ubiquitous in nature and are found in variety of environments ranging from soil, sand, marshes, brackish water, sea and fresh water. Most of them are capable of manufacturing their own food.

Microalgal research is offering wide potential in food biotechnology and is gaining more attention because of presence of wide range of bioactive and nutraceutical properties and added health benefits.The increasing population is one of the major growing concerns of today’s world. To meet the nutritional requirement of the rising population, researchers are looking for optional sources for food which are easy to cultivate, cost effective and produce large amount of bioactive compounds useful to prevent major diseases. Chlorella is unicellular green alga that is a potential source of nutrients like carotenoids, minerals, vitamins, and polyunsaturated fatty acids. Especially, omega-3 fatty acid and carotenoids have received considerable interests due to their roles in the prevention of chronic diseases. Lutein and zeaxanthin from Chlorella have been shown to be associated with eye health and function. Beta-carotene is known to reduce the risk of CVDs and certain cancers. Animal studies also demonstrated that Chlorella supplementation reduced the serum cholesterol levels.

Similarly, the blue green microalgae Spirulina, possesses diverse biological activities and nutritional significance. Regular consumption of Spirulina fortified food improves immune system by increasing phagocytic activity of macrophages, stimulating the production of antibodies and cytokines, increase accumulation of NK cells into tissue and activation and mobilization of T and B cells. Spirulina have also shown to perform regulatory role on lipid and carbohydrate metabolism by exhibiting glucose and lipid profile correcting activity in experimental animals and in diabetic patients. They were also found to be active against several enveloped viruses including herpes virus, cytomegalovirus, influenza virus and HIV. They are capable to inhibit carcinogenesis due to antioxidant properties.

1. Introduction

Fruit products have their unique identities having large content of micronutrients, polyphenols, vitamins, flavonoids and other nutritional compounds. Characteristic appearance and flavors distinguish among various fruit based products like juice, puree, jam, jelly, squash and other several varieties. Main concern of this fruit processing industry is the stability of the products throughout the post processing storage. Thermal treatment as mean of preservation of these products is the common process implemented so far. It ensures the safety of the product but lacks in retaining the nutritional intact that like of fresh fruit. Today’s consumer demand for minimally processed fruit products and “natural” fruit products tend to think of alternative thermal processing.

High pressure processing (HPP), a relatively new concept compared to conventional thermal processing, also sometimes known as high hydrostatic pressure (HHP), or ultra high pressure (UHP) processing, is a non-thermal food processing method that subjects liquid or solid foods, with or without packaging, to pressures ranging between 50 and 1000 MPa. HPP has already been established itself as an alternative to thermal processing. In food processing it is of great interest due to its ability to inactivate food borne microorganisms and enzymes, at low temperature, without the need for chemical preservatives and it is less detrimental than thermal processes to low molecular weight food compounds such as flavoring agents, pigments, vitamins, etc., as covalent bonds are not affected by pressure. Pressure-treated foods have sensory properties similar to fresh products, which is a major advantage in fruit processing as it matches consumer demand for healthy, nutritious and ‘‘natural’’ products. HPP of fruit products offers the chance of producing food of high quality, greater safety and increased shelf life (Hayashi 1989; Gould 1996; Butz and Tauscher 1998).

1. Introduction

The demand for non-dairy based beverages in form of non-dairy milk is on rise due to several reasons. Firstly, the prevalence of lactose intolerance and milk allergy amongst a major percentage of population who cannot consume dairy milk and look for alternate source of proteins. The need for functional drinks is also a major factor which contributes to the increase in demand of milk-alternatives. It has also been reported that milk processors around the world face an uphill battle, including the dominance of private labels; consumer concerns over the presence of growth hormones in non-organic milk; fluctuations in commodity prices; supply shortages for organic milk; and growing consumer concern about the safety of animal products in general. With that long list of challenges, the market has had few growth opportunities even though consumers continue to prize milk for its nutritional benefits.

2. Need for Non-dairy Beverages

2.1 Prevalence of lactose intolerance

Lactose intolerance is estimated to affect 33 % of the global population, but the prevalence of the condition varies from country to country. It is also estimated that an average of 75 % of human adults have decreased intestinal lactase activity after weaning (NDDI, 2012).

1. Introduction

There is a general consensus that fruit and vegetable consumption is a key factor for a balanced diet. Globally, majority of people consistently are consuming less than the daily recommended fruit and vegetable requirement. Even in developed nations e.g., Australia, Canada, Europe, UK and USA, researchers have concluded that there is large gap between actual and recommended consumption of both fruits and vegetables despite decades of concern and publicity while resultant outcomes were short-lived. In a study from 52 low and middle-income countries 77.6% of men and 78.4% of women consumed less than the minimum recommended servings of fruits and vegetables. Same study reported 74% low fruit and vegetable consumption among adults in India (Hall et al., 2009). In India, recent studies on the fruit and vegetable intake amongst urban residents was reported as 265 g per day as against 400 g per dayof fruits and vegetables excluding potatoes and other starchy tubers, that is recommended by the World Health Organization (WHO, 2008).

Epidemiological studies conducted in recent years have indicated a positive correlation between the consumption of fruits and vegetables and prevention of cancer and cardiovascular diseases. Health-promoting functional characteristics of vegetables are mainly attributable to their functional bioactive constituents. These effects can be listed as antioxidant activity, cholesterol-bindingcapacity, antidiabetic activity and angiotensin-converting enzyme (ACE) inhibitory activity. Studies conducted in cell culture models and animal models have revealed that bioactive compounds of plant foods, including soybean, hawthorn fruit, tea, buckwheat, oats, onion, garlic, almond, and vegetable juice, composed of tomato watercress, parsley, carrots, celery, lettuce, beets and spinach, have cholesterol-lowering activity (El-Shatanovi et al., 2012; Vadivel et al., 2011).

1. Introduction

Now a days, foods are not intended to only satisfy hunger and to provide necessary nutrients but also to prevent nutrition-related diseases and improve physical and mental well-being of the consumers (Menrad, 2003). In this regard, functional foods play an important role. The concept of functional foods which has evolved as the role of food in the maintenance of health and well-being and in the prevention of disease, has received increased scientific and commercial interest is recent past. Growth of functional foods markets include increased consumer health awareness, increased popularity of healthy foods, search for food-based drug substitutes, self-medication approach promoted by busy lifestyles and rapidly developing health conscious markets. Functional foods can be defined as foods “that can beneficially affect one or more target functions in the body, beyond adequate nutritional effect, in a way relevant to an improved state of health and wellbeing and/or reduction of risk of disease” (Stanton et al., 2005).

1. Introduction

Milk and milk products constitute essential dietary components for a vast majority of the population. India with annual production of more than 135.6 million tonnes has emerged as leading milk producing nation. The per capita per day availability of milk in India is more than 290 g. Buffalo milk accounts for 57% of the total milk produced in India. Ethnic dairy products account for 90% of all dairy products consumed (Aneja et al., 2002). Many health benefits have been attributed to fermented dairy products and probiotic microorganisms (Salminen et al., 1998). The market for functional foods, nutraceuticals, wellness foods and beverages is fast growing. The harmful effects of synthetic drinks have propelled health conscious consumers to go for natural and traditional drinks. In search of better returns, the Indian dairy industry is widening its focus to include traditional milk products, and these are emerging as new profit centres for the organised sector.

Traditional dairy products have several advantages. They require low capital investment and give high profit margin. They are more appealing to the Indian palate. Dahi or curd is the most popular indigenous fermented dairy product. There are numerous references to dahi in vedic literature. The Prevention of Food Adulteration Act (Anon, 1976) describes dahi as a product obtained from pasteurized or boiled milk by souring (natural or otherwise), using harmless lactic acid or other bacterial cultures. Indian dahi and its western counterpart yoghurt differ considerably in terms of cultures used and their bouquet and flavour profiles (Aneja et al., 2002). The major flavor compound in dahi is diacetyl. Dahi made from buffalo milk has a firm body and white glossy appearance, with a cream layer on top. Mixed mesophilic cultures of Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp diacetylactis along with Leuconostoc species are grown together for production of dahi.

1. Introduction

Fermented milk products such as yoghurt are produced through out world (Kurmann et al., 1992). Yoghurt can be characterized as a gel like coagulated milk product, having a smooth consistency and a pleasing flavour and is now widely consumed both by infant and adult populations. It is common that yogurt preparation involves the use of equal amounts of two lactic acid bacteria (LAB): Streptococcus thermophillus (St) and Lactobacillus delbrueckii ssp. bulgaricus (Lb); samples prepared with these starter bacteria are labeled Lb-St (Ng et al., 2011). In the early stage of the incubation process, Lb stimulates the growth of St releasing amino acids from casein (where the most important is valine) and producing a moderate reduction in pH due essentially to St. Yoghurt has better digestibility than milk and this is related to its comparatively high content of free amino acids. Besides nutritional value, it possesses hypocholesterolaemic (Mann, 1977) and antitumour effects (Odd et al., 1983; Reddy et al., 1983).Yoghurt may be set or stirred and has a potential for being used as dietary supplement for infants. So they cross the line between dietary supplements, health foods and conventional foods with great facility. Now a days, emphasis is given on sweeteners and more natural sweeteners will be used (Hollingsworth, 2001). Natural sweeteners can be easily incorporated in yoghurt by blending cattle milk with fruit pulps like mango. The enhancement of other nutrients e. g. vitamins and minerals will be added advantage. Mango pulp which contains a high proportion of sugar, mostly monosaccharide, is easily adsorbed by the digestive systems (Celik and Bakirci, 2003).

Soybean is a comparatively inexpensive source of high quality protein. The protein and fat contents in soybean are above 40 % and 20 %, respectively. Nutritionally, soy protein is a more balanced plant protein for human consumption. Studies have indicated that consumption of soy protein decreases total serum cholesterol and minimizes risks for several cancers (Anderson et al., 1995; Messina, 1997; Zind, 1998). The positive health benefits associated with soybeans have greatly increased its consumer awareness which has created a large market for soy foods (Ohr, 2000; Liu, 2000). The problem of beany flavour in soy products can be overcome by lactic acid fermentation (Buono et al., 1990; Granata and Morr, 1996). Soy solids are not only abandoned source of protein but also have therapeutic properties against breast, prostate, colon and lung cancers due to its isoflavones like genistein and daidzein content. Fortification with soy made yoghurt beneficial in lowering cholesterol level and blood pressure and in relieving symptoms of menopause and osteoporosis.

1. Introduction

Extrusion is one of the most preferred ways for creating the indulgence called ready-to-eat (RTE) snack foods with diverse shapes, sizes, colours and also nutritional and functional values which appeal to the diverse group of consumer with varied choices. In this chapter ready-to-eat extruded and puffed snacks are the focus covering the technology involved, criteria for ingredient selection, design of experiment, process modelling, effects of extrusion on physical, nutritional and functional quality of the snack; a few relevant case studies are also discussed.

1.1 Market for RTE snack foods

Indian cooking and lifestyle have undergone tremendous changes in the last 15 years. There are many major factors impacting this change which include, liberalization policy, dual income, separate living of couples, innovative kitchen applications, media proliferation, etc. The cooking style and eating habits in India varies drastically from southern part to northern part of the contry. Due to lifestyle pressure nowadays people prefer easy short way of cooking food rather spending too much time on cooking. Rapid urbanisation is also one of the reasons for people to buy such products. Snack foods comprise a very large variety of items including potato chips, crackers, nuts and extruded snacks, among others (Harper, 1981). Snack food extrusion includes subjecting selected raw material to a variety of complex physical processes to yield snacks with varied shapes and textures (White, 1994).

The RTE market in India was expected to expand to reach Rs. 2,900 crore by 2015, according to an analysis done by Tata Strategic Management Group (TSMG). The products may vary from noodles, pasta, masala packages, stuffed paratha, etc. and many more. There are many regional players who are making foray into ready-to-eat segment. Many national and international players like Nestle, Pepsico, ITC, Haldirams, Cavinkare, are already in Indian market with their products.

1. Introduction

1.1 Malnutrition

The term malnutrition generally refers both to under nutrition and over nutrition, but in this guide we use the term to refer solely to a deficiency of nutrition. Many factors can cause malnutrition, most of which relate to poor diet or severe and repeated infections, particularly in underprivileged populations. Inadequate diet and disease, in turn, are closely linked to the general standard of living, the environmental conditions, and whether a population is able to meet its basic needs such as food, housing and health care. Malnutrition is thus a health outcome as well as a risk factor for disease and exacerbated malnutrition, and it can increase the risk both of morbidity and mortality (Ogunrinade, 2014). A term used to refer to any condition in which the body does not receive enough nutrients for proper function. A person cannot properly digest or absorb nutrients from the food they consume, as may occur with certain medical conditions (Medicine, 2015). Malnutrition may range from mild to severe and life-threatening. It can be a result of starvation, in which a person has an inadequate intake of calories, or it may be related to a deficiency of one particular nutrient (for example, vitamin C deficiency).

Malnutrition is estimated to contribute to more than one third of all child deaths, although it is rarely listed as the direct cause. Lack of access to highly nutritious foods, especially in the present context of rising food prices, is a common cause of malnutrition. Poor feeding practices, such as inadequate breast feeding, offering the wrong foods, and not ensuring that the child gets enough nutritious food, contributes to malnutrition (WHO, 2015).

Pooled estimates report the prevalence of malnutrition among community-dwelling older adults of 6% and among hospitalized older adults of 39%. In developed countries, treatment of malnutrition is relatively inexpensive and effective: energy and protein supplementation using commercial “sip feeds” results in both weight gain and reduced mortality (Pereira et al., 2015). In 2013, one in four children under age five worldwide had stunted growth. Between 2000 and 2013, stunting prevalence globally declined from 33 to 25 %, and the number of children affected fell from 199 million to 161 million. In 2013, about half of all stunted children lived in Asia and over one third in Africa (UNICEF, 2015). Malnutrition may be several types as follows:

1. Introduction

1.1 Engineered health rice

Rice is one of the leading food crops in the world and sustains two-third of the world’s population providing 20% of the world’s dietary energy supply. It can be polished and marketed as white rice or can be marketed with the bran layer left intact as brown rice. The dry grain can then be steamed or boiled by the consumer to rehydrate and cook it (Kato, 2006). Despite its primary importance as a staple food, rice has several disadvantages. Primarily, rice is low in protein and high in starch. The low protein levels in rice can lead to protein malnutrition in societies where rice is the primary constituent of the diet. Deficiencies in essential amino acids may also result from a diet primarily comprised of rice. For example, lysine is the essential amino acid found in the lowest quantity in rice. The human body needs lysine for proper growth and repair of tissues. It is also important in the production of various enzymes, hormones and disease-fighting antibodies (Kato, 2006). The production of broken rice is nearly 15-20% of total production of rice (Bhullar and Bhullar, 2013). The broken rice is generally used for rice flour production and Indian traditional foods such as Idli, Dosa and weaning foods etc. Ugwu et al., (2012) reported that the rice broken can be utilized for the production of poly (3-hydroxybutyrate). The major value addition of broken rice is possible by reconstructing it into rice-shape and fortifying it with desired nutrients or micronutrients, which is a big challenge in terms of making the product acceptable to the consumers.

One approach to overcome the above mentioned challenges is to prepare artificial rice kernels or rice analogues by extrusion, in which the vitamins are embedded and consequently do not separate from the rice grains. This will utilize mainly the broken rice which is either discarded or sold at subsidized prices as the cattle feed. Furthermore, embedding makes extraction of the vitamin by rinsing or cooking more difficult and may provide a certain protection against oxidation, because the vitamins can be enveloped by a protective matrix (Steiger, 2010). The fortification of commercially produced staple foods allows exposed populations to benefit without making major changes to their eating habits (Kunz, 2009).The rice analogues prepared from extrusion can be used by addition of an appropriate proportion of water at a temperature ranging from 90°C-100°C, whereupon the rice product rehydrates within three minutes to obtain a product having the desired appearance and organoleptic properties to simulate natural rice grains (Harrow and Martin, 1982).

1. Introduction

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in genetically susceptible individuals. Gluten is the protein component in wheat, rye and barley. In the last 10 years, cutting edge scientific developments in this disease have led to the formulation of new concepts of epidemiology, pathophysiology and clinical manifestations. At present, the only available treatment for CD is a strict gluten-free diet (GFD) (Mulder et al., 2013; Theethira and Kelly, 2014). Until recently, the geographical distribution of CD was mostly restricted to Europe and other developed countries, such as the United States, Canada and Australia. Celiac disease is not only frequent in developed countries, but it is increasingly found in areas of the developing world, such as North Africa (Malekzadeh et al., 2005), Middle East (Rostami et al., 2004) and India (Basu et al., 2014, Deora et al., 2014; Yachha and Poddar, 2007). New epidemiological studies have brought evidence that this disorder is common in many developing countries as well, showing that the ‘global village of celiac disease’ has indeed a worldwide distribution (Fasano and Catassi, 2001).

The only available treatment for celiac disease is the strict, lifelong avoidance of gluten. When gluten is removed from the diet, the small intestine will start to heal and overall health should improve (Fasano and Catassi, 2001). Traditional substitutes for gluten-containing grains have been rice, tapioca, corn, and potato. However, more nutrient-dense grains, seeds, nut flours, and legumes are being incorporated into the diet to provide an enhanced palatability, variety, and nutritional quality. These include sorghum, millet, teff, quinoa, amaranth, flax seed, and buckwheat.

1. Introduction

The development of food products using composite flour has increased and is attracting much attention from researchers, especially in the production of bakery products and pastries. This article focuses on the use of composite flour to produce food products, namely bread, biscuits, and pasta, with looks at on its impact, following some improvements made, on the sensory quality, rheology characteristics, and nutritional values as well as its overall acceptance. The blending of wheat flour with various sources of tubers, legumes, cereals and fruit flour in different percentages to produce variety of food products are also reported. The positive effects of the use of composite flour can be seen in the final product related to the functional and physicochemical properties and health benefits of raw blended flour along with percentage blending. Overall, composite flour is a good new approach to utilizing uncommon food products as the application of composite flour produced products with different characteristics and quality, depending on the types and percentage of wheat flour used in the formulation.

Bread has been the staple food worldwide and habit of bread is derived in part due to the convenience and wholesomeness. Wheat is a commonly used cereal for making bread as it gives the desired texture due to the presence of gluten forming proteins like gliadins and glutenins (Decock & Cappelle, 2005). In earlier times idea of composite flour in developing countries originated in order to cut down on import of wheat (as it was not grown in many countries) but in recent past refined wheat flour consumption has lead to health issues and thus in order to improve nutritional and functional properties composite flour has been the norm. Composite flour is the one obtained by mixing wheat flour with cereal and legume flours for making bread and biscuits (Dendy, 1992). However, mixing of non-wheat flours, roots and tubers, legumes or other raw materials can also be regarded as composite flour.

Though the pesticide application represents viable solution to pest control, however indiscriminate use poses threat to target as well as non-target crops. The side effects of pesticides therefore have to be considered based on their use and on the agricultural system to which particular pesticide is used. Studies should be implied on effects and persistence of pesticides in crops and is consequent effects on soil microbial flora and associated nitrogen metabolism. Safe alternate methods like development of relatively cheaper biopesticide should be encouraged. More efficient methods have to be developed and validated for dissipation of pesticide residues in food grains. Human health and environment has gained great importance in the modern world. The widespread use of insecticides has resulted in problems caused by its interaction with the natural biological systems. Study showed that higher amounts of acetamiprid have some negative effects on corn plant physiology. Thus, the use of pesticide should be controlled following the standards of developed countries to protect health and the environment.

Partitioning of assimilated carbon among sink organs is a critical factor that controls the rate and pattern of plant growth. Environmental stress often restricts resource availability while successful acclimation sets in motion processes that restore the supply. A key mechanism contributing to regulation of carbon partitioning is an expression of genes that control activity of the enzymes which initiate sucrose metabolism at specific sites and stages of ontogeny. Drought stress not only limits the size of the source and sink tissues but the phloem loading, assimilate translocation and dry matter portioning are also impaired. However, the extent of effects varies with the plant species, stage, duration and severity of drought. Crop production faces many challenges, due to changing environmental conditions and evolving needs for new plant-derived materials. 
The extreme temperatures those are consequences of present-day global climate changes are considered as major abiotic stresses for crop plants. Temperatures exceeding the limits of adaptation substantially influence the metabolism, viability, physiology, and yield of many plants. Plants exposed to extreme temperatures often show a common response in the form of oxidative stress. However, the extent of damage caused by extreme temperatures depends greatly on the duration of the adverse temperature, the genotypes of the exposed plants, and their stage of growth. Numerous research findings support the notion that induction and regulation of antioxidant defenses are necessary for obtaining substantial tolerance against environmental stress. Plant adaptation to either high temperature or low temperature is a multigenic response which is very complex in nature. Plant response to continuous light depends on plant tolerance and can be modified by alteration in temperature, light intensity, CO2 level, and other environmental factors.

Plant–water relations concern how plants control the hydration of their cells, including the collection of water from the soil, its transport within the plant and its loss by evaporation from the leaves. Flow of water through plant and soil over macroscopic distances is driven by gradients in hydrostatic pressure. Over microscopic distances it is driven by gradients in water potential. Evaporation of water from leaves is primarily controlled by stomata, and if not made good by the flow of water from soil through the plant to the leaves, results in the plants wilting. Plant water deficit is initiated as the crop demand for water exceeds the supply. The capacity of plants to meet the demand and thus avoid water deficit depends on their “hydraulic machinery.” This machinery involves firstly the reduction of net radiation by canopy albedo, thus reflecting part of the energy load on the plant. Secondly, it determines the ability to transport sufficient amount of water from the soil to the atmosphere via the stomata in order to provide for transpiration, transpirational cooling and carbon assimilation. Water is transported by way the soil-plant-atmosphere continuum and it is largely controlled by the resistances in the continuum as determined by root, stem, leaf, stomata and cuticular hydraulic resistances. The gross effects of deficient and of excessive soil moisture on plant growth are well known, but controversy has existed for many years around the question whether the so-called “‘available moisture” is equally available for plant growth or available only with such increasing difficulty that plant growth functions are retarded before the wilting point is reached. Various measurable aspects of plant growth do not respond in the same manner to increasing moisture stress. Crops will respond to irrigations, although measured soil moisture stress is quite low. Problems of relating plant growth to soil moisture stress conditions varying with both time and soil depth are considered. Soil factors affecting density or depth are reviewed and several ways weather factors influence soil, -moisture-plant-growth relations summarized.

Marginal land areas will need to be used to meet the increasing requirement of future generations, especially in developing countries. These marginal areas commonly impose abiotic stresses on crops due to factors such as salinity, drought, flooding, low nutrients and aluminium or heavy metal toxicity. As a consequence, the growth and yield of crops from such areas is typically low and their quality in also poor. Endogenous plant growth regulators play an important role in regulating plant responses to abiotic stress by sensitizing growth and developmental processes. While the physiological and molecular mechanisms linked to the role of ABA and cytokinins in stress tolerance are well explained, there is growing interest to elucidate the associations of auxins, ethylene, gibberellins, brassinosteroids, and polyamines in stress tolerance mechanism and also on possible cross talk mechanism among different growth regulators during stress tolerance acquisition. Identification and characterization of the gene regulating synthesis of different endogenous growth regulators and recent progresses on hormonal signaling, mutant research, and physiological actions have provided scope for manipulating their biosynthetic pathways for developing transgenic crop plants with enhanced abiotic stress tolerance. Researches have also provided some leads in exploiting the potential of growth regulators in enhancing the resistance to abiotic stresses of crops. Plant growth-regulators (PGRs), are biochemical and chemical compounds stimulates plant growth and productivity when applied, even in small quantities at appropriate plant growth stages. These are being extensively used in agriculture to enhance the productivity in agricultural crops. Their central role in plant growth and development is through nutrient allocation and source-sink transitions while most of the plant bioregulators (PBRs) stimulate redox signaling under abiotic stress conditions.

We do not know when intercropping began nor why early civilizations fostered its use. Whether by design or accident, intercroppinq dominated early agriculture and is still practiced in many areas of the world. With the advent of “modern” agriculture, intercropping began disappearing from many areas. This shift was driven primarily by mechanization and specialization. Despite pressures to abandon intercropping, it has survived and flourished Inereasing interest in sustainability and environrnental concerns have drifted attention back to intercropping as a means of better utilization of resources while preserving the environment.
Through intercropping, farmers can achieve the full production of the main crop and also an additional yield (bonus) associated with an increased plant population of the second component. Hence, intercropping can increase incomes obtained by smallholder farmers in areas where labor is not shortage, through reduction of economic risk and market fluctuation resulting from growing a single crop which is more prone to natural hazards and helping the farmers in better utilization of land by having more than one crop produced per unit area. Though all intercrops produced higher productivity, the farmers could better use the appropriate population of component crops in intercropping systems in order to maximize yield of both crops as well as total productivity. It is, therefore, important to support intercropping systems with appropriate agronomic practices such as timely irrigation, pest protection and the likes to sustain the cropping system in the countries where labor is not problem for proper management in general even though sometimes sole cropping may became more productive.

Most food legumes have a long history of domestication almost as long as cereals, and during this time they have been subjected to conscious and unconscious selections for better adaptation to environmental condition as well as better seed yield. In general, crops during their ontogeny faces a number of abiotic stress viz., excessive and/or low soil water stress, soil salinity stress, high as well as low temperature stress. It has been well documented that crop yields would be greater in many cropping regions if more water were available. 
Availability of water for agriculture is being challenged increasingly because of growing demand for water from other sectors such as industry, urban use, and for social and environmental purposes. Water stress may conceivably arise either from an insufficient or from an excessive water activity in the plant’s environment. Many physiological characteristics are correlated with the water potential of mesophyll tissue but the correlations are species specific. There is a general hierarchy of sensitivities among general physiological activities. Most sensitive are cell expansion, cell wall synthesis, protochlorophyll formation, and nitrate reduction. Generally turgor pressure is still accepted as the best indicator of water stress in plants. The specific mechanism by which turgor regulate physiological function probably relate to cell walls and membranes. Cell membrane structure, and spatial arrangement of enzyme, transport channels, cellulose synthesis rosettes, and receptor proteins may be dependent on turgor pressure.

The extreme temperatures those are consequences of present-day global climate changes are considered as major abiotic stresses for crop plants. Different studies clearly show that temperatures exceeding the limits of adaptation substantially influence the metabolism, viability, physiology, and yield of many plants. Plants exposed to extreme temperatures often show a common response in the form of oxidative stress. However, the extent of damage caused by extreme temperatures depends greatly on the duration of the adverse temperature, the genotypes of the exposed plants, and their stage of growth. There is ample need to develop temperature tolerance in crop plants by exploring suitable strategies. Numerous research findings support the notion that induction and regulation of antioxidant defenses are necessary for obtaining substantial tolerance against environmental stress. The development of genetically engineered plants, by the introduction and/or overexpression of selected genes, would to be one feasible strategy. However, plant adaptation to either high temperature or low temperature is a multigenic response which is very complex in nature. Thus the task of identifying the traits those correlate with stress tolerance is incredibly difficult for researchers. Plant response to continuous light depends on plant tolerance and can be modified by alteration in temperature, light intensity, CO2 level, and other environmental factors.

The stresses, drought, salinity, chemicals, cold and hot temperatures, have interconnected effects on plants, resulting in the disruption of protein homeostasis. Maintenance of proteins in their functional native conformations and preventing aggregation of non-native proteins are important for cell survival under stress. The heat shock proteins buffer this environmental variation and are therefore important factors for the maintenance of homeostasis across environmental regimes. Heat shock proteins are known to be expressed in plants experiencing high-temperature stress. Heat shock proteins are important in relation to stress resistance and adaptation to the environment. Their molecular function might be membrane or protein stabilization, but, for now, for most heat shock proteins the molecular function remains to be elucidated. The general observation of the response and induction of heat shock proteins following heat stress suggests that they play a fundamental role in cellular homeostasis. It is possible that heat shock proteins may be involved with the phenomenon of acquired thermotolerance. Heat stress disturbs cellular homeostasis and can lead to severe retardation in growth and development, and even death. Temperature stress can have also a devastating effect on both the plant anabolism and catabolism, initially acting on protein complexes, being the quaternary structure the first folding that is lost during heat stress or heating. Understanding the role of HSPs in relation to stress resistance in a more applied perspective as a potential indicator of stress is important. New technological developments make it possible to investigate the role of genes coding for heat shock proteins in greater detail. A combination of genomics and proteonomics will further elucidate the effects of stress on expression patterns at the DNA, RNA and protein level.

Plants that are affected by various abiotic stresses react differently as a result such as the reduction in organ size or a change in the antioxidant enzyme system, and while drought and heat are often studied separately, in nature they often occur together, meaning it is essential to carry out joint studies. Furthermore, and related to the above when we consider high temperature stress, one must always consider the use of water and nutrients by the plant and other physiological functions. The effects of heat stress can also be analyzed by the technique that measures lipid peroxidation in polyunsaturated acids of the plasma membrane. The accumulation of metals in plants, affects the normal processes of plant metabolism. The study shows that there is a relationship between high metal contents in plants and their modified morphology: strong reduction of leaf thickness, modified parenchyma structure, and decreased mitochondria organization were ascertained, although toxic symptoms were apparently absent. Water-deficit stress has a significant effect on plants growth and development, with primary affects on plant structure, leaf morphology and cell ultrastructure. Physiological processes such as stomatal conductance, photosynthesis and respiration are consequently impaired with further implications on the metabolic functions such as carbohydrate and energy production as well as carbohydrate translocation and utilization.

Abiotic Stress in Plants
             
World population is growing at an alarming rate and may reach about 6 billion by the end of the year 2050. Though, the agricultural productivity is also being increased world over, yet it is not keeping pace to meet the demand of food availability. The main reasons for limiting the agricultural productivity are water shortage, depleting soil fertility and mainly various abiotic stresses and climatic change. Minimizing these loses is of primary concern for all nations to cope with the increasing food requirement. The abiotic stress is defined as the negative impact of non living factors on the living organism in a specific environment and abiotic stress is the most harm full factor concerning the growth and productivity of crops worldwide. Researches have shown that abiotic stressors are at their most harm full when they occur together in combination of abiotic stress factors (Mittler, 2006; Bianco and Defez, 2011). Numerous stresses caused by complex environmental conditions i.e. drought, too high and too low temperatures, freezing, salinity, UV light, heavy metals and recently through smog (air pollution) leading to substantial crop losses worldwide (Mahajan and Tuteja, 2005). The abiotic stresses might increase in the near future even because of global climatic change.

Climate change drastically influence water availability, salinity and several adverse soil conditions which will have direct bearing on original yields. Abiotic stress factors influence growth and secondary metabolite production in higher plants. The influences are well marked. In fact, productivities depend on the changed ecosystem also. Secondary metabolites play a major role in the adaptation of plants to the changing environment and in overcoming stress constraints. This flows from the large complexity of chemical types and interactions underlying various functions: structure stabilizing, determined by polymerisation and condensation of phenols and quinones, or by electrostatic interactions of polyamines with negatively charged loci in cell components, photoprotective, related to absorbance of visible light and UV radiation due to the presence of conjugated double bonds, antioxidant and antiradical, governed by the availability of –OH, –NH2, and –SH groupings, as well as aromatic nuclei and unsaturated aliphatic chains, signal transducing. Several plant-abiotic stress stimuli systems evidenced the multiplicity of biochemical mechanisms involved in the protective role of secondary metabolites:

Environmental stress can disrupt cellular structures and impair key physiological functions. Drought, salinity, and low temperature stress impose an osmotic stress that can lead to turgor loss. Membranes may become disorganized, proteins may undergo loss of activity or be denatured, and often excess levels of reactive oxygen species are produced leading to oxidative damage. As a consequence, inhibition of photosynthesis, metabolic dysfunction, and damage of cellular structures contribute to growth perturbances, reduced fertility, and premature senescence. Responses to environmental stresses occur at all levels of organization. Cellular responses to stress include adjustments of the membrane system, modifications of the cell wall architecture, and changes in cell cycle and cell division. In addition, plants alter metabolism in various ways, including production of compatible solutes that are able to stabilize proteins and cellular structures and/or to maintain cell turgor by osmotic adjustment, and redox metabolism to remove excess levels of ROS and re-establish the cellular redox balance. At the molecular level, gene expression is modified upon stress and epigenetic regulation plays an important role in the regulation of gene expression in response to environmental stress.

Sweet pea (Lathyrus odoratus) is the only species in the genus Lathyrus and family Fabaceae which is widely cultivated as an ornamental plant. Lathyrus comes from the Greek word “Lathyros” in which the prefix “la” means “very” and suffix “thyros” means “passionate”. The “Odoratus” is derived from Latin word which means “fragrant” (Fernald, 1950). It is mainly grown for its beautiful flower colour forms. It is an annual climbing plant growing to a height of 1-2 m with the support of a terminal tendril which twines around the plants and helps to climb. The illness caused by the ingestion of sweet pea is known as odoratism or sweet pea lathyrism. Sweet pea was used to verify Mendel’s work with the garden pea (Pisum sativum L.) in the early 1900s (Bateson, 1902). The genetical phenomenon of linkage was first demonstrated in the sweet pea. It is used prominently as a model organism to study flower development due to its large, colourful and fragrant flowers. The essential oils extracted from the sweet pea can be used in perfume blends.

ORIGIN AND DISTRIBUTION

Sweet pea (Lathyrus odoratus L.) was discovered in Sicily in 1695 (Rice, 2002). Its species are found both in the Old World and the New World. The main centres of diversity are the Mediterranean region, Asia Minor and North America as well as temperate South America and East Africa (Kupicha, 1977, Jackson and Yunus, 1984, Yamamoto et al., 1984 and Simola, 1986). It generally grows in temperate regions and has been found on all continents except Antarctica (Kenicer et al., 2009 and Kenicer et al., 2005). Its cultivation is popular not only in the United Kingdom and the United States but also in Europe, Russia, Egypt, New Zealand, Australia and Japan (Hambidge,

1996, Inoue, 1981, 2007 and Rice, 2002). There are some reports of commercial sweet pea cut flower production (Hammett, 2006, Inoue, 1981 and Parsons, 2004). A seed bank at the Chichester Collection was started in 1998 and stores around 900 cultivars and around 100 accessions of other species.