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“Standards are to Industry as Culture is to Society” said Shri C. Rajagopalachari, the first Governor General of India. Shri C. Rajagopalachari was inaugurating a conference on Standardization and Quality Control in February 1948. The great statesman has beautifully summed up the importance of standardization.

The basic principles on which procedures and practices are based had their origin in the United Kingdom, where the first national standardization movement started as early as 1901. Thereafter, procedures have been continuously developed, modified and improved till considerable similarity is achieved.

The scientific community working in the field of crop protection is experiencing an increasing academic and industrial interest in the discovery and development of new bio-insecticides as environmentally friendly pest control tools to be integrated, in combination or rotation, with chemicals in pest management programmes. In this context, Entomopathogenic nematodes (EPNs) as a bio-control agent have proven successful and are now commercially mass produced in six of the seven continents to treat pest problem in agriculture, horticulture and forest crops. They actively search for the host, including those in cryptic habitat stages of insect pests in soil environment. They can be considered as good candidates for integrated pest management in ustainable agriculture due to plants and mammals which are not adversely affected and have ease of mass production. We present a general overview on the current state of knowledge of EPN and their mutualistically associated bacteria and their utilization as biological control agent against insect pests in world and India are briefly presented in this chapter.

Endophytic Microorganisms

Endophytes (‘endo’, inside; ‘phyte’, plant) include microorganisms that thrive inside the plant tissues without any obvious adverse effects on the host, and they include mainly bacteria and fungi (Hallmann et al., 1997; Bacon et al., 2002; Hardoim, 2015). Endophytic microorganisms share an intimate association with the host adding essential and functional capabilities. Therefore, plant may be considered as a superorganism composed of an amalgam of both selected symbiont microbiota and host cells (Hardoim, 2015) with the new concept of holobiome, i.e., plant together with the associated microorganisms collectively governing the plant activities (Hardoim et al., 2015; Vandenkoornhuys et al., 2015).

The shift from vegetative to reproductive phase in plants is the result of multiple gene cascades in response to photoperiodic and temperature dependent pathways, gibberellic acid pathway, vernalization pathway and autonomous pathway. The environmental cues are initially detected in the leaves and the mRNA of the flowering signal integrator FT gene, moving to the shoot apical meristem, acts as a long-distance signal for floral meristem identity. At SAM, FT-FD protein complex, based on signals from above said pathways in association with the signals from age-dependent and miRNA pathways, leads to the activation of master regulator gene of flowering AP1. The activation of genes involved in ABCDE model of floral organ differentiation, based on the directions of various cadastral genes lead to the development of floral organs. Thus, the sequential action of floral meristem identity genes, floral organ developmental genes, floral meristem size and organ number genes, floral organ pattern genes and cadastral genes leads to the flower development. This chapter sums up the gene interactions happening in leaf and SAM, leading to the development of a complete flower.

Today it has been understood that yeasts have great potentials as novel probiotics (Nayak, 2011). They have been found to be safe for human consumption in traditional fermented foods (Jakobsen and Narvhus 1996). Yeasts have a great physiological importance inside the gastrointestinal (GI) tract (Czerucka et al., 2007; Gatesoupe, 2007). Jespersen (2003) has mentioned the role of consuming fermented foods and the health benefits attributed with it.Yeasts are known for prevention of table olive (Arroyo lopez et al., 2012). Bonatsau et al. (2015) have shown multi-functional property of yeast as starters.

In spite of the problems with dosage and viability of probiotic strains, a lot more work is required for industry standardization and safety issues. However, it is noted that probiotics have considerable potential against many pathogenic and other diseases. A wide range of clinical trials are still needed to standardize and optimize the conditions. Ongoing basic research will continue to identify and characterize existing strains of probiotics, identifying strain-specific outcomes, determine optimal doses needed for certain results and assess their stability through processing and digestion.

What new research is needed, what trials and how will the ultimate consumer and Industry benefit?
 
In Brazil, the sales of functional foods amounts to US $ 500 million per year representing about 1% of the total sale of the Brazilian food processing industry. According to a report the interests are mainly for dairy products, nutraceuticals and soy-based products. ABIA forecasts a substantial growth of 4.5-5% for this segment of the market (Stanton et al., 2001). In order to exert the health benefits beyond inherent basic nutrition, it is necessary that the activity of the probiotic culture should be maintained at very high levels during the shelf life of the product.

Probiotics are measured in colony forming units (cfu). CFUs are generally measured in the millions or billions per serving. Probiotics are most commonly beneficial bacteria, but can also be friendly fungal or other organisms, that are typically freeze dried to stabilize them in an inert state during storage and production. Then their continued stability and viability, as measured by CFU counts when cultured, is dependent on limiting their exposure to stimulating environmental conditions such as temperature and moisture. Besides refrigeration, this protection can be done by packaging in glass or by adding freshness packets that helps to absorb and reduce moisture in the package.

Antibiotic Resistance and Gene transfer
 
It is important that probiotic strains should be assessed for their phenotypical antibiotic resistance and potential to transfer resistance gene as otherwise they cannot be used in food (BgVV, 2000; Vankerckhoven et al., 2008). It is vital to do research on characterization of acquired resistance mechanisms and transferability of resistance genes and on methods for determining transferability.

Probiotic Fermented food products
 
An individual requires adequate nutrients like proteins, carbohydrates, vitamins, and minerals to maintain diet. There has been an explosion of the consumer interest in the role of enhancing the health by some specific foods or physiologically active food components, so called functional foods (Hasler, 1998). The concept of functional foods evolved in the year 1990 in Japan.

The lack of mechanistic understanding of probiotic activity is a major drawback for the prediction of safety of probiotic intervention. The complex gut-associated microbial ecosystem and nutritionally related factors are the most important environmental triggers for the development and modification of chronic degenerative diseases including immune and metabolic pathologies. In fact, the interaction between the gut microbial ecosystem and the host is considered to be a critical factor in overall health or disease. Whether probiotics will exert protective, harmful, immune-stimulating or immune-suppressing effects on a host is dependent on the interaction between the microbial signals, the genetic make-up of the host and the effects by the environment. Many studies have revealed that certain probiotic bacteria stimulate immune cell proliferation and activity as evidenced by the production of cytokines and antibodies, thereby enhancing the effectiveness of the immune response against pathogens. Ng et al. (2009)

4a. Intestinal Disorders
 
History of health claims
 
According to Bottazzi (1983) it was in 76 BC that the Roman historian Plinius recommended the use of fermented milk for treating gastroenteritis. Metchnikoff claimed that the intake of fermented milk containing Lactobacilli reduces the toxin producing bacteria, thereby increasing the longetivity of the host (Metchnikoff, 1908). Tissier (1905) showed that there was an increase in the Bifidobacteria in breast fed-infants, thus claiming that the administration of Bifidobacteria to infants suffering from diarrhea was very beneficial as they supersede the putrefactive bacteria that causes the disease. Intestinal beneficial microfloras are responsible to resist the disease (Bohnhoff et al., 1954).

LAB constitutes a group of gram positive bacteria. They are nonsporulating, nonrespiring but aerotolerant cocci or rods, which produce lactic acid as one of the main fermentation products of carbohydrates, they do not have cytochromes. They belong to the phylum Firmicuttes, class Bacilli and order Lactobacillaceae. The group includes several genera such as Lactobacillus, Lactococcus, Bifidobacterium, Pediococcus, Enterobacter, Corynebacterium, Streptococcus, Leuconostoc etc.

There are potential beneficial medicinal uses of probiotics for which research is limited and only preliminary results are available. Recent research on the molecular biology and genomics of Lactobacillus has focused on the interaction with the immune system, anti-cancer potential, and potential as a biotherapeutic agent in case of antibiotic-associated diarrhoea, traveller‘s diarrhoea, pediatric diarrhoea, inflammatory bowel diseases and irritable bowel syndrome (Ljungh et al., 2009). Studies of some probiotics tested in vitro on human epithelial cell lines have shown that they could block the adhesion of shiga toxin producing E. coli (Sherman et al., 2005). These are claimed to be health promoting and/ or disease preventing beyond the basic function of supplying nutrients. Probiotic foods are emerging as an important category of food supplements. Earlier workers have shown the inhibition of diarrhea caused by E.coli using probiotic lactic acid bacteria and yeast (Yan and Polk, 2006). Ratledge et al. (2002) have studied the biochemistry and molecular biology of lipid accumulation in oleaginous microorganisms.

Newer technologies involve fermentation by specific strains of lactic acid bacteria which bring specific fermentation under controlled conditions to a specific fermented product with enhanced organoleptic, nutritional and therapeutic qualities. Today health is of primary concern. It is important to have nutritionally balanced food with good bacteria. For this, probiotic foods top the list. The functional food concept was initially developed in Japan in 1990‘s as there were many side effects of allopathic medicines. A regulatory system has been initiated by the ministry of health and welfare to approve certain foods to improve health. These are now recognized as Foods for specialized health use (FOSHU). According to American dietic association (ADA) these foods are potential healthful food or food ingredients that may provide health benefits beyond the traditional nutrients. Probiotics are beneficial microorganisms. Probiotic foods as yogurt and sauerkraut are very well known. Fermentation increases the nutrient content and taste with the shelf life.

National Horticulture Board

Commercial floriculture includes production of cut flowers, foliage plants, bedding plants and growing and forcing bulbs and corms of flowering plants for whole and retail sales. The floriculture industry has become highly specialized. Floriculture industry uses many devices to ensure steady supply of flowers and foliage plants irrespective of the season and minimum loss to industry, because of perishable nature of flowers.

Today, floriculture has transformed into a viable agri-business. Estimated area under flower growing in India is about 65,000 ha. More than two-third of this area is devoted for the production of traditional flowers. Production of cut flowers comes to about 500 million numbers. The interesting aspect is that 80% of Indian exports consist of only roses. Other major cut flowers include gladiolus, tuberose, carnation and orchids. With the emerging trends and constant urge for new innovative products, it is high time that Indian floriculture industry shifts towards new or novelty crops (Singh, 2005).

Tuberose (Polianthes tuberosa) commonly called as Rajanigandha produces waxy, white and fragrant flowers on long spikes which are mostly used as cut flowers for making garlands and extracting essential oil. Among the ornamental bulbous plants, it has great economic potential for cut flower trade and essential oil industry. The predominant characteristics of this crop are its lingering, delightful fragrance and excellent keeping quality.

Rose the ‘Queen of flower ’is undoubtedly the world’s most favourite and popular romantic flower. It occupies a prestigious position in cut flower industry and as a garden plant. For thousands of years, the rose has been a symbol of love, adoration, innocence and all other virtues. Countries like England adopted rose as their national flower. In India, rose adorned the gardens of not only the rich and the famous, but also the ashramas of the saints. Rose cultivation initially developed with the distillation of rose for essential oil. Today the importance of rose is in its value as a cut flower. It is one of the most important commercial flowers throughout the world. Roses are also used for preparation of rose water and ‘Gulkhand’ 

Orchids are the royalty among flower crops. They exhibit an incredible range of diversity in size, shape and colour of flower. They are valued as cut flowers and potted plants and are the most pampered plants. Orchid flowers are famous for the long lasting characteristics and bewitching beauty. No other plant has probably acquired the status of orchids. They have always been considered as mysterious plants.

Marigold is one of the easiest annual flowers to cultivate, having wide adaptability. Flowers are attractive, have good keeping quality with a wide spectrum of colour, shape and size. They produce marketable flowers in a short time and are used widely for religious and social functions as well as for garden display. 

Importance and Uses

 Marigolds are sold as loose flowers, as cut flowers and widely used for various decorations and garland making. They are also excellent landscape plants widely used for bedding purpose, in herbaceous borders and can also be grown in pots. French marigolds, being dwarf, are suitable for hanging baskets, rockeries, edging and window boxes. In fact, marigolds rank next only to jasmine in popularity in South India 

Jasmine (Jasminum spp) is one of the oldest fragrant flowers cultivated by man. They are the most common flowers in India gardens.

Importance and Uses

They are traditionally important flowers not only as fresh flowers but also as source of high grade perfume oil. Mention of jasmine is there in ancient Indian literature like Kamasutra (AD 300-400) and Mahabharatha (500 BC). The odour of jasmine flowers cannot be imitated by any known synthetic chemical or natural isolates, thus giving it a unique status in the perfume world.

Heliconias are tropical plants of princely dimensions grown for their attractive foliage and brilliant flower spikes. They are some of the most unusual flora of the tropics. Strikingly elegant flower heads rise from banana like clumps of oval leaves, which are sometimes rather slender and, with a few varieties, extremely large. They are found naturally in the tropical forests world wide and in moderate climates. A popular landscape plant and cut flower in tropical and subtropical areas of the world, heliconias are native to Central and South America, the Caribbean Islands and some of the islands of the South Pacific. Their easy cultivation and spectacular presence have made them favourite garden subjects throughout the world. Heliconias have several common names including lobster’s claw’s, ‘parrot’s flower’, ‘parrot plantain’ and false plantain. Depending on variety, heliconias will range in height from 60 to 700 cm, often with extensive rhizomatous growth. The flower or inflorescence of heliconia is nearly always terminal and may last from several days to several months. They are particularly desirable as cut flowers because of their long lasting characteristics. 

Gladiolus is a flower of breathtaking beauty with a wide range of colours, size and form. Its magnificent inflorescence has won for it, a place of pride in gardens and value as a cut flower. Except true blue and green practically all colours are available in gladiolus. Flowers are long lasting and stand transport well. They are widely used in flower arrangements, bouquets and indoor decorations. It is estimated that gladiolus is grown throughout India over on area of 1270 ha (Arora et al. 2002).

Gerbera, commonly known as Transvaal Daisy, Barberton Daisy or African Daisy, is cultivated throughout the world under a wide range of climatic conditions for its attractive flowers. It is highly suitable for beds, borders, pots and rock gardens. The wide range of colour and the attractive shape of flowers suit very well in flower arrangements. The cut blooms have long vase life. Today Gerbera is known as an important commercial flower crop and belongs to the most important plant species in the world, together with the rose, chrysanthemum, carnation and tulip. Gerbera is amongst the ten most important commercially grown flower crops in the world.

Chrysanthemum (chrysos =golden; anthos = flower) is a popular flower crop of commercial importance known as the “Queen of the East”. It ranks next only to rose among flower crops in the world.

China aster (Callistephus chinensis) belonging to family Asteracea is a native of China. It is a half hardy annual, erect plant, hispid hairy branches bearing alternate, broadly ovate or triangular ovate, deeply and irregularly toothed leaves. Flowers are solitary, usually blue, lavender rose or white coloured. China aster is one of the most important among garden annuals grown throughout the world. Among annual flowers China aster ranks third next to chrysanthemum and marigold. It is grown by small and marginal farmers in Karnataka, Tamil Nadu, West Bengal and Maharashtra. Due to its long vase life, China aster is a popular cut flower used in vases and for floral decoration and also for making garlands and venis in Karnataka. Asters are popular as bedding plants and used to fill gap in mixed herbaceous borders. Dwarf cultivars are also suitable for edging and window boxes.

Carnation is one of the important cut flower crops grown throughout the world and occupies prime position because of the attractive colour, shape and good vase life. Due to the excellent keeping quality, wide range of forms, ability to withstand long distant transportation and remarkable ability to rehydrate after continuous shipping, carnation is preferred by growers to roses and chrysanthemums in several flower exporting countries.

Although cut carnations are sold in western countries all the year round, they are in particular demand for the Valentines Day, Easter, Mothers Day and Christmas. While standard carnations are in great demand, the miniature types are fast gaining popularity for their potential role in floral arrangement and also as cut flower at comparatively low price. White and pink standard carnations are in the greatest demand followed by red, yellow and bicolour. The liking for a colour depends upon the time or season. The re standard types are preferred to other colours, especially during the Christmas. In contrast in miniatures, the terminal flower bud is pinched to encourage clusters of short-stemmed small flowers. These types are mainly used for flower arrangement. (Bhatt, 1989)

Anthuriums are tropical flowering plants with attractive foliage. These flowers are bewitchingly beautiful with attractive form and long lasting characters making it a favourite choice for flower arrangement and for bouquet making.  Anthurium is a large neotropical genus of 600-800 species belonging to family Araceae. Two flowering species in this genus Anthurium andreanum and Anthurium scherzerianum are extremely fascinating and commercially important.  The flowers of anthurium are popular with flower arrangers because of their bold effect and lasting qualities (Bhatt and Desai, 1989 and Singh, 1995). Together with some of its many hybrids, A. andreanum today forms the basis of a substantial cut flower industry chiefly in Hawaii, where much research is done in its hybridization and cut flower.

Bonsai culture is an important branch of Ornamental horticulture. History of Bonsai is very old dating back to many centuries in China where it originated, as most Chinese arts and from there it spread to Japan and became highly specialized.  In fact, bonsai culture is in the present day more known as Japanese than as a Chinese art.  In Japanese homes, there are plants which are hundreds of years old. This treasured art is passed from generation to generation in Japanese society.

The word Bonsai is a combination of two Japanese words, Bon (meaning shallow pan) and Sai (meaning plant) which can be interpreted as ‘Tray planting’.  The idea conveyed is that of a small beautiful tree growing in a container as in nature with all its parts performing their natural functions throughout the times.  The artistic look of plant in a miniature form maintained for many years is the prime criteria.  Bonsais are grown outdoors and are displayed in living room, as and when, needed.  They cannot be treated as house plants.

Dry flowers are naturals, dried and preserved with an everlasting value the can be cherished for longer period. According to APEDA investigations, dried flowers accounted for 15% in the total floriculture export during 1988-89 and increased to 64% in 1994-95. Export value of dried plants and planting materials increased from Rs. 109.21 million in 1993-94 to Rs. 364.55 million in 1995-96.
 
India exports dry flowers to U.K., Germany, Italy, The Netherlands, U.S.A., Japan and Singapore. Dry flower production is labour intensive, provides self-employment and job opportunities for a large number of workers and aids in development of subsidiary industries. The industry has many advantages.

A ‘flower’ is an intricate organ composed of different morphological units including sepals, petals, androecium, gynoecium, stem and leaves. These units differ functionally with each other which ultimately decide the longevity of flowers. A cut flower may be defined as flower or an inflorescence containing more than one floral unit in the opened or unopened state which is harvested and marketed for ornamental purposes. Cut flowers in general are highly perishable commodities and highly vulnerable to huge post harvest losses. Once severed from the plant, they are deprived of their natural sources of water and nutrients and they wilt rapidly. It is claimed that 70% of the potential lasting quality of cut flowers is pre-determined at harvest. While post harvest factors influence 30% of the effects nearly 20-80% of the cut flowers are lost due to improper post harvest handling (Salunkhe et al., 1990).

Orchids belong to family Orchidaceae, which is the most highly evolved among monocotyledons with over 800 genera and 35,000 species and over 74,400 natural and manmade registered hybrids. Orchid is the first horticultural plant cloned by tissue culture methods on a commercial scale (Goh, 1990). Rapid multiplication using tissue culture techniques is an important strategy for preserving the valuable orchid wealth in India. Vegetative propagation through division of rhizomes and separation of offshoots and keikis is very slow. Both these problems can now be successfully alleviated through micropropagation. The technique has revolutionized the orchid industry and now it is possible to multiply unlimited number of desirable clones. Rotor (1949) was the first to have employed tissue culture techniques to multiply Phalaenopsis, and since then micropropagation potential of a variety of monopodial taxa has been successfully tested.

Seed is a vital input for successful flower production and it is considered as the starting material for most bedding plants and many of the cut flowers produced. The production of bedding plants and cut flowers is both capital and labour intensive. In order to optimize production efficiency and maximize profit, it is important for growers to use high quality seeds. Production of seeds of annual flowers has immense scope as an area of diversification in floribusiness. The flower seed industry is international, operating in many countries of the world. Large quantities of flower seeds are required both by developed and developing countries for adding to the beauty of private and large gardens and also for cut flower production. Worldwide, nurseries engaged in production of seeds of seasonal flowers have a booming business. The great diversity of flower seed crops is a fascinating facet of the world seed industry and they are of high value and low volume in contrast to the high volume and low value seeds of cereal seed crops.

Indian floriculture industry is shifting from traditional flowers to cut flowers for export purpose. The liberalized economy has given an impetus to Indian entrepreneurs for establishing export oriented units (EOUs) under controlled climatic conditions.

The wide variation in the agro climatic conditions in India permit us to grow various types of tropical and subtropical plants and flowers. Though such plants grow successfully without cover, they fail to meet the export requirements of being seldom blemish free. High quality ornamental plants meant for export should be scientifically grown only in plastic, glass or fiberglass greenhouses, or at least under partial cover. Though initial investment is high in protected cultivation, the products in them will obtain far more attractive prices.

Floriculture  is  increasingly  regarded  as  a  viable  diversification  from traditional field crops due to increased per unit returns and increasing habit of “saying it with flowers” during all the occasions. All over the world, the floricultural sector is experiencing rapid changes. Opening up to the world, market  in  the  WTO  regime  paving  way  to  free  movement  of  floricultural products worldwide, globalization and its effect on income generation have all  contributed  to  increase  in  per  capita  consumption  of  flowers  in  most countries. Noticeable  feature  of  global  floriculture  is  the  development  and expansion of floriculture in non-traditional areas. Netherlands, Italy, Germany and  Japan  had  strong  tradition  for  growing  and  consumption  of  flowers. The  concept  of  commercial  floriculture  was perpetuated  across  the  world from those regions. New production centres are developing in Latin America, Africa and also in Asia to meet the demand of consuming countries and also to  expand  domestic  market,  commensuration  with  improved  economic conditions  these countries  provide  highly  qualitative  floricultural  products with low cost price which is finding a favourable place in markets of Western Europe, America and Japan. Emergence of new production centres has made floriculture  more  competitive  and  this  in  turn  is benefiting the  ultimate consumers.

Quality is an increasingly important factor in the production and marketing of biological products. Consumers are becoming more discerning as their affluence increases, and would be suppliers of products must meet these demands if they are to maintain or increase market share. The term ‘quality’ is one of the most defined terms in use in food industry today. Quality may be defined as ‘The totality of features and characteristics of a product that bear on its ability to satisfy a given need’. The first part, ‘The totality of features and characteristics of a product…..’ concerns objective factors related to the product.  The second part, ‘…… to satisfy a given need’, concerns subjective factors related to user or consumer of goods.

Transportation and distribution of fruits and vegetables are important stages   of post-harvest loss. In India,  transportation of perishable commodities is in the most precarious stage. For local market, the produce is brought either by bullock cart or tractor trollies. The long distance transportation is mainly by rails and trucks, which is very costly. The basic reason for preference to road transportation is that it takes short transit period.

Packaging is an integral part of fruit and vegetable processing. It has  major influence on storage life and on marketability of fresh as well as processed products. Packaging fulfills several functions including containment, facilitating transportation, protection of fruit/vegetable from further damage, protection of environment from contents of package (for example, if the contents are dirty), marketing, product advertising, and stock control.

Minimally processed fruits and vegetables are products that have the attributes of convenience and fresh like quality. Their forms vary widely, depending on nature of unprocessed commodity and how it is normally consumed. In many cases, minimally processed product is raw and cells of tissues are alive, but these characteristics are  not regarded as essential. It is important that products have fresh-like character, regardless of   state of cells.  Minimally processed products for both retail and food service applications have increasingly appeared in market place recently.  In coming years, it is commonly perceived that this industry will have unprecedented growth.

Fermentation was known to mankind from time immemorial. But, development of biochemical principles of  fermentation  was originated by  Lavoisier in France in 1789 by way of analysing chemical composition of  sugar and its fermentation products such as ethanol, carbon dioxide and  acetic acid. Many products are produced by fermentation process. In fermentation, controlled action of selected microorganisms is used to alter  texture of foods, preserve foods by production of acids or alcohol or to produce fine flavours and aromas which increase value of raw materials.

Fruit beverages

Fruit beverages are highly refreshing, thirst quenching, appetizing, easily digestible and nutritionally far superior to synthetic drinks. The fruit beverages includes natural and sweetened juices, squash, syrup, cordial, nectar, Ready to Serve (RTS) beverages, fruit juice concentrate and citrus juice barley water. Fruits most commonly used to prepare beverages are oranges, lime, pineapple, grapes, cashew fruit, mango, jack fruit, apple etc. To prepare fruit beverages select fresh, fully ripe, tart, juicy and seasonal fruits.

The technique of preserving fruit by the use of low temperature dates from the eighteenth century with the first use of ice house in 1750. Later in 1800s commercial cold storages have come up for the storage of perishables like meat, dairy and fruit products.  The main change took place in the cold store in recent years has been the introduction of multi temperature chambers with humidity control for specific products. Cold preservation can be either refrigeration or freezing. Household refrigerators usually run at 4-7^ºC. Chilling or cold storage usually uses a slightly lower temperature on the basis of the food to be refrigerated. In freezing a temperature of -18^ºC or below is used. Chilling will preserve perishable foods for days or weeks and freezing will preserve foods for months or even years.

Drying is the oldest known method of preserving food. Drying or dehydration is removal of majority of water contained in fruit or vegetable. Although preservation is the primary reason for dehydration, it also lowers cost of packaging, storing and transportation by reducing both weight and volume of final product. In addition, dried foods add variety to our diets. In the process of drying, sufficient moisture is removed to protect product  from  spoilage. Processing should be done in such a way that food value, natural flavour and characteristic cooking quality of fresh material are retained after drying.

Processing of fruits  and vegetables into various products which could be preserved for a long time and add to value of product using proper cost effective technology will be a viable tool for improving   economic status of  farmer as well as our country. Modern methods of fruit and vegetable preservation are  broadly classified as follows:

Storage is one of the most important aspects of post harvest handling of fruits and vegetables. The main objective of storage is to extend storage life of fruits and vegetables and increase their period of availability. A substantial quantity of fruits go waste in India due to lack of proper storage facilities. Storage of fruits and vegetables is practiced for various reasons. Proper post harvest handling of fresh horticultural produce helps in extending  period of availability of wide range of  fruits and vegetables round the year, prevention of seasonal market gluts, orderly marketing, better return to grower and  preservation of  nutritional qualities. The   long  term  storage  of  fruits  and  vegetables is expensive and requires high level of technical  knowledge of crop. However, an orderly marketing reduces storage period considerably. 

Various systems were developed to take produce from field to consumer and selection of a particular method depends on several factors, including perishability and value of crop.  One method is to harvest the crop and take it to a packhouse for various unit operations like grading, cleaning, post-grading treatments, and packing for transport and marketing. When deciding upon where to locate a packinghouse, access to field and market point, adequate space for vehicles to enter and leave  packinghouse and ease of access to labor will all be considered.
 
In the simplest packinghouse, produce is delivered in picking containers, immediately after harvest, directly to packers.  Packers then sort, grade, size and pack the produce directly into appropriate transport containers. In this case, each worker must be aware of produce defects, grade and size requirements, and packing methods.

Maturity at harvest is the most important determinant of storage life and final fruit quality. Maturity indices are determined for many fruit, vegetable and floral crops. Harvesting crops at proper maturity allows handlers to begin their work with the best possible quality produce. Produce harvested too early may lack flavour and may not ripen properly, while produce harvested too late may be fibrous or over ripe.
 
Almost all fruits reach their best eating quality when allowed to ripen on the tree or plant (exceptions e.g., pears, avocados, and bananas). In general, fruits become sweeter, more colourful, and softer as they mature. A few fruits are usually picked mature but unripe so that they withstand post harvest handling system when shipped long distances.  Most of  currently used maturity evaluation is based on a compromise between those methods that would ensure the best eating quality and those that provide flexibility in transportation and marketing.  Optimum harvesting stage depends upon type of fruit or vegetable and their final use. Such a division is usually based on their classification according to physiology, environmental conditions, ripening bahaviour and nutritional aspect. Some of the classifications, important for their harvesting and storage are briefed in  subsequent sections.

Structure

Structural unit of edible portion of most fruits and vegetables is the parenchyma cells and makes up bulk of cells. A parenchyma cell is rather thin walled and may be polygonal or cubical in shape.  Walls of parenchyma cells in young plants are composed almost entirely of fibrils of cellulose. In parenchyma cells of plants actively metabolising protoplast portion represents only about 5% of total cell volume. This protoplast is rather film like and is pressed against cell wall by large water filled central vacuole.  Protoplast has inner and outer semi permeable membrane layers between which is confined cytoplasm and its nucleus. 

Fruits and vegetables are very important food commodities. India has become the largest producer of fruits and the second largest producer of vegetables. Though the production of fruits and vegetables make us believe in our strength for self-sufficiency, a significant qualitative and quantitative loss occur in the produce from harvest till consumption.  For self sufficiency and also for processing, export and to meet additional requirements, a lot of emphasis need to be given to reduce post harvest losses, besides increasing  production and productivity of horticultural produces. Processing plays an important role in  conservation and effective utilisation of these perishable commodities. However, only less than 2% of total production of fruits and vegetables are processed.  The new industrial policy has placed this sector in the list of high priority areas.