Milk is considered an ideal food for neonates, adolescents, adults and geriatrics and hence every attempt has been made by mankind to preserve this wholesome food by various processing operations. In the recent decade, the focus of attention has been on improving the quality, particularly sensory, nutritional and functional qualities of foods and at the same time, minimizing the processing and post harvest losses through technological and biotechnological interventions. Recent advancements in dairy technology have also offered the opportunity not only to control the existing food processes in better way, but also to adopt entirely novel approaches to quality control and newer product development. Meanwhile, an ever-increasing variety of specialized dairy products from whole and skim milks to creams, cheeses, yoghurts, whey products and specialty powders are opening up tremendous opportunities for growth. In search of efficiency, the dairy industry, a major sector of the food industry at a national level, is constantly seeking to improve the working practices, and the advances in process technology are an integral part of this trend.

Fat-rich dairy products such as cream, makhan, butter, butter oil and ghee have played a pivotal role in growth and development of dairy industry in India as well as abroad from the time immemorial. The reference of makhan and ghee has been found in old Indian scriptures. Makhan was popularized by Lord Krishna about 5000 years before. In the traditional Indian dietary regimen, milk fat in the form of malai (cream), makhan (freshly churned butter) contributes significantly towards nourishment of people of almost all ages. Indian dairy industry, over the years, has been converting surplus milk for the manufacture of fat-rich dairy products, especially ghee and butter with skimmilk as a byproduct because of technological and economic reasons. More than one-third of the total milk production is being utilized for the production of ghee and butter wherein milk lipids, the most expensive constituents of milk are conserved and preserved. Milk lipids play many diverse roles, some of which are essential for human health. Many of the desirable flavour and textural attributes of dairy products are due to their lipid components, consequently, butterfat has, traditionally, been highly valued. Significance of fat can also be realized from the fact that the consumer’s perception of food quality is largely based on the perceivable rich taste. Unfortunately, milk lipids are subject to chemical and enzymatic alterations which can cause flavour defects referred to as oxidative and hydrolytic rancidity, respectively. The storage stability of high-fat products is strongly influenced by these changes.

2.1. The Story of Fermentation Human progress depends on man’s tact to tame the forces of nature. It calls for knowledge. Prior to Age of Science, our fund of such knowledge was gained by a process of trial, error and accidental discovery. Progress was due not so much to man’s understanding as it was to his unquenchable spirit, miraculous ingenuity and indomitable persistence. At last, in the utmost urgency of struggle for a longer, healthier and more satisfying existence, humanity taught itself the scientific method, which has changed the world, and will change it more in the coming years. This chapter deals with one of the most momentous and far reaching of all scientific achievements: the ability to harness microscopic living creatures in the service of mankind. Thanks to the wonders of fermentation technology and biochemical engineering developed by scientists and skilled technicians in industrial, governmental and university laboratories around the world, billions of microbes are now at work in industry, producing substances that give us better food $#x0026; drink, better clothing $#x0026; shelter and better medicines. Thus, the human race has entered a new era of health, comfort and longevity. In the Beginning Art without Science: The cave man discovered that meat allowed to stand a few days was more pleasing to the taste than meat eaten soon after the kill. The cave man’s earliest descendants learned that intoxicating drinks could be made from grains and fruits.

Starter cultures were unknown until 1878, when Lister isolated pure cultures of the lactic acid bacteria responsible for milk acidification. In the 1980s, improvements to standardization and ripening of butter were made by introducing pure starter cultures. During the period 1910-20, Orla-Jensen, von Freudenreich, Sherman, Hammer and other dairy microbiologists prepared pure cultures for fermented milks. Commercial production and use of starter cultures grew rapidly and was widespread at the beginning of the 20th century. Dairy starters are the ‘heart’ of fermented milk products, the most crucial component in the manufacture of high-quality fermented milks. The cultures are harmless food-grade microorganisms, active bacteria intentionally grown in milk or whey or other formulated media which impart desirable and predictable flavour and texture to fermented dairy products. The dairy microorganisms employed in milk fermentation are single-strain or multiple-strain cultures of lactic acid bacteria, producing different types of fermented milk products. Usually, one or two strains dominate the milk environment. Individual strains can be selected in advance for their resistance to both bacteriophages and antibiotics. Mixed starter cultures are used to ensure that fermentation will continue after a bacteriophage attack. Bacteriophages are highly strain-specific, and if the dominant strain in a mixed-strain starter culture succumbs to an attack, the phage-resistant mutant or the next dominant culture maintains a satisfactory rate of lactic acid production.

Cheese is a milk product of ancient origin and portrays the ethos of civilization and its cultural evolution. Cheese is one of the oldest foods of mankind. It is commonly believed that cheese evolved in the Fertile Crescent between the rivers Tigris and Euphrates in Iraq some 8000 years ago. The so-called Agricultural Revolution occurred here with the domestication of plants and animals. It seems that the cheese originated accidentally as a result of the activities of nomadic tribes. Since animal skin bags were a convenient way of storing liquids for nomadic people, these were used for storing surplus milk. Fermentation of the milk sugars in the warm climate prevailing would cause the milk to curdle in the bags. The swaying animals would have broken up the acid curd during journeys, to produce curds and whey. The whey provided a refreshing drink on hot journeys, while the curds, preserved by the acid of fermentation and a handful of salt, became a source of high protein food supplementing the meager meat supply. This activity gave rise to the assumption that cheese was evolved from fermented milks. It is perhaps more probable that the crude fermentations progressed in two ways. In one direction towards the production of liquid fermented milks such as dahi, yoghurt, laban, koumis and Kefir and in the other direction through the drainage of whey through a cloth or perforated bowls, to leave solid curds which when salted became cheese. It was a prominent article of the Greek and Roman diet as much as 2500 years ago. It is referred to in the Old Testament several times.

Heat desiccated products represent khoa and khoa-based sweets, rabri, basundi, etc. These are important traditional dairy products. Traditional dairy products and a great assortment of sweets is an integral part of Indian heritage. These products are endowed with enormous value and enjoy tremendous mass appeal. Of great social, religious, cultural and economic importance these products have been developed over a long period of culinary skills and carry with them, the age-old wisdom and experience. Traditional dairy products have always played a pivotal role in preservation of precious milk nutrients and promotion of its consumption among masses. The increased availability of milk during the flush season coupled with lack of facilities to keep liquid milk fresh during transit from rural production areas to urban market has led to the conversion of milk into variety of traditional products. In addition to preservation of milk solids for longer duration, manufacture of traditional dairy products adds value to milk and also provides tremendous employment opportunity. It is estimated that about 50% of milk produced in India is converted into a variety of traditional products. Traditional dairy products represent the most prolific segment of Indian dairy industry. These products not only have an established market in India but also have a great export potential because of strong presence of Indian diaspora in many parts of the world. In view of the growing awareness towards the safety aspects of milk-based sweets in India, the consumer shall prefer to buy these products from the organized sector. Despite the widespread popularity and acceptability of traditional milk products in the Indian market, the organized sector has so far not been able to tap into this market potential for many reasons such as lack of published literature on their technology, inadequacy of appropriate technologies for their commercial exploitation, inadequacy of appropriate packaging materials and labeling to take care of new pattern in consumer demand, low keeping quality and a lack of quality assurance systems.

Milk may be concentrated as a necessary initial step in drying operation or as concentrating step in the manufacture of sweetened condensed milk or evaporated milk or the preparation of infant formulae. In order to preserve the milk constituents in a concentrated form, condensed milk/concentrated milk is manufactured from whole skim milk by removing or evaporating part of the water under vacuum. But this form of milk still has limited shelf life. Attempts to prolong the shelf life of this product have been made through the addition of bacterial growth inhibitor like sugar (sweetened condensed milk) or by heat processing (evaporated milk) to destroy the microorganisms. Concentrated milk industry is an important segment of dairy industry. It plays an important role in the economy of industry. It serves as a balanced economy. It utilizes surplus milk in the flush season. It utilizes abundant milk production in certain localized area. It makes use of surplus milk below excellent grade. By either concentrating or drying less space is needed to store and it becomes less bulky and therefore it can be transported to any part of the world. The keeping quality of milk is increased. The concentrated products give considerable saving in the cost of packaging, storage and transportation. Milk concentrates can be easily reconstituted with required amount of water corresponding to that removed by evaporation to yield a product having normal consistency of milk. It is estimated that nearly two per cent of the world’s milk production is converted into different types of condensed or concentrated milks. Brief history and developments: The present day concept of preservation of milk by concentration and by application of heat had the beginning with the pioneering work of French man Nicholas Appert around 1793. Gail Bordon of USA was first to commercially exploit the method of concentration of milk under vacuum. He was awarded U.S. Patent in the year 1856 for processing milk in a semi-fluid state after evaporating under vacuum. Commercial production of sweetened condensed milk by Gail Bordon started in 1856.

The method of preserving various food stuffs by drying them, and thereby depriving microorganisms of the water necessary for their growth, has been known for centuries. According to Marco Polo’s accounts of his travel in Asia in 13th century, soldiers of Kublai Khan carried dried milk on excursions. Before it was used, water was added to a portion of dried material. Mixing was accomplished by movement of the horse during riding on the trip. The recombined product was then consumed at the mealtime. The belief is that part of the fat was removed from the milk before drying and dehydration was accomplished by solar heating. Drying is defined as the removal of the liquid, usually water, from a product by evaporation, leaving the solids in an essentially dry state. Today the production of dried milk and milk products has become important segment of dairy industry. Dry milk provides a means of preserving the excess milk supply during the flush season for use during the lean season. The value added dried dairy products like malted milk foods, infant food and infant formulae and dairy whiteners are convenient ready to use products having wide acceptance. The water content of milk powder ranges between 2.5 and 5%, and no microbial growth occurs at such low water content. Drying extends the shelf life of milk, simultaneously reducing its weight and volume. The main purpose of drying milk are: a) to improve the storage life of the product due to low moisture content, b) to reduce cost for storage and transportation of product due to reduced bulk, and c) to provide convenient product for utilization in many dairy and food preparations. The production of dried milks to a great extent is now being governed by the market requirement and to some specialized use of such products. Considerable quantities of dried skim milk powders are being used extensively in the preparation of ‘Reconstituted and Recombined milks”. Milk powders are also used extensively in the manufacture of ice cream, bakery products, confectionary products, cottage cheese and in other cheese varieties. The greatest proportion of milk powder is utilized in confectioneries, such as milk chocolate, caramels, soft sweets, coatings, biscuits and cakes. In these products, milk powder has a special effect on the quality of particular products: it improves consistency, flavour as well as nutritional value and shelf life.

Ice cream over the years has come to acquire an easy acceptance as a healthy, nutritious and hygienic food for the aged, sick, growing children and adults. Its popularity, as demonstrated on all types of occasions is growing fast and its potential appears to be unlimited. Gone are the days when the word “Ice Cream” was synonymous with strawberry and vanilla flavours or the innocuous orange. Ice cream is available in many forms, flavours and packages. Today, there are exotic variations to titilate the palate, such as Jingle Bells, Goody goody Gum Drops, Champagne Snowballs, Mr. Frost, Tutty Fruity, Butter Scotch, etc, waiting to launch customers on a gastronomical voyage. It is uncertain how long ice cream has been produced, however, the International Association of Ice cream Manufacturers (1966) traces the beginnings of ice cream and frozen desserts to iced drinks enjoyed by Alexander the Great in the fourth century B.C. down through the years Nero in the first century A. D., Marco Polo in the 13th century through Italy and France to England in 1643-1649, and to America around 1700. From a very old writings it has been learnt that the Chinese liked a frozen product made by mixing fruit juices with snow, what we now call water ice. It is believed that ice cream evolved from iced beverages and water ices that were popular in the medieval period. This technique later spread to ancient Greece and Rome, where the wealthy, were partial to frozen desserts. After disappearing for several centuries, ice creams in various forms reappeared in Italy in the Middle Ages, most probably as a result of Marco Polo returning to Italy in 1295 after a 16-17 year stay in China, where he had learnt to appreciate a frozen dessert based on milk. There is no gainsaying the fact that the true origin of ice cream cannot be proclaimed with a fair measure of certainty but, all the same, the Italians claim that Benaroo Bountalenti, a resident of Tuscany, invented ice cream in the early 1300s. From Italy ice cream spread over Europe during the 17th century, and for long remained a luxury product for the royal courts. Italian ice cream was very popular in London around 1870.

Dairy byproducts constitute an important segment of dairy industry. An important criterion in the economic choice of any process is the efficient utilization of byproduct that is produced along with the main product. The main byproducts of dairy industry are skim milk, buttermilk, whey and ghee residue. Each and every component of milk must be judiciously processed into edible form not only to improve the profitability of dairy industry but also to make best use of the unique nutritional value of the precious milk constituents on one hand, and to prevent environmental pollution, on the other. However, dairy plants, particularly in India, are usually confronted with the problem of byproduct utilization, especially that of whey and ghee residue in economical manner. Skim milk is a byproduct obtained during the manufacture of cream. It is rich in solids-not-fat content and has high nutritional value. In dairy plants, it is mostly utilized either in standardization for the manufacture of main dairy products or preserved by removing moisture in milk powder form. The skim milk when utilized in either of these two forms or consumed as liquid, is not considered a byproduct. It is regarded as a byproduct only when it is either not economically utilized or utilized for derived byproducts, like casein and other related products, co-precipitates, protein hydrolyzates, etc. Buttermilk is the byproduct obtained during butter manufacture. Sweet cream buttermilk resembles skim milk in gross chemical composition and is usually admixed with bulk of skim milk for further spray drying or even product manufacture in dairy plants. Desi buttermilk, on the other hand, has long been an important domestic beverage in India. It has high nutritive and therapeutic value. It also finds its way in the preparation of a host of culinary dishes such as kadhi, dhokla and idili. Also a number of federations and private plants sell salted and spiced buttermilk in 200 ml pouches.

Introduction In terms of individual health and physical condition, the situation in modern society is rather giving rise to concern. The last decades have seen a tremendous increase in availability and variety of food products which has undoubtedly affected the food habits of the average individual. Despite the fact that food has become overall safer and increased accessibility allows for healthier diets, worrying we are nevertheless faced nowadays with diet- related diseases of proper epidemic proportions. We now encounter an epidemic of obesity that spreads not only to the majority of the adult population but also, more worryingly, to young people who have rarely the option of alternative diets. Moreover, as scientific proofs for the link between diet and disease (particularly cardiovascular diseases and some cancers) accumulate, action is urgently needed. There are an increasing number of calls for action. It is within this situation that functional foods have developed. They assume a highly targeted solution to the diet related diseases with effective reduction of risk and improved physical and mental well being. That represents a big step from the traditional food-for-nutrition but the scientific milieu is ready to take the chances. The emerging ‘functional food science’ is focusing research on the effects of functional foods on growth, development, metabolism, the cardiovascular system, intestinal physiology, and even on behavioural and psychological functions (FAIR, 2000, Vol. 1). In view of these facts, it should appear necessary to assess and evaluate the developments in food production in terms of their effect on the individual consumer and the society at large.

There is no single factor as important in the production of fine quality dairy products as absolute and complete cleanliness. R.B. Barrett It is not enough to provide milk for man, it must be high quality milk. It would be impossible to provide man with milk and milk products of superior quality if we were unable to remove milk soil and to kill residual microorganisms. Respectively, these are the processes of cleaning and sanitizing. To successfully provide the atmosphere for proper food safety, the basics must be thoroughly understood. The basics of food safety begin with good understanding of sanitation processes, food-handling procedures that protect from, or eliminate cross contamination problems and specific attention to inspection of and follow up for all processes. Food safety activities need to be programmed into available time of day scheduling just as production requirements do. Whether special personnel or separate shifts handle cleaning responsibilities or you clean as you go on the production line, time must be made available. Safe products leaving the facility must be the watch word of all employees involved with the process. In order to ensure safe food supply a high level of sanitation should be maintained throughout the food production chain. The word ‘sanitation’ is derived from the Latin word “sanitas” which means “health”. To further apply this word to the food industry, sanitation is the creation and maintenance of hygienic and healthful conditions when processing, preparing and handling food. Sanitation is the application of science to provide wholesome food handled in a hygienic environment by healthy food handlers to prevent contamination by food spoilage microorganisms. Effective sanitation refers to the mechanisms, which accomplish these goals.

We all are familiar with the word “quality”. If we bring some fruits or vegetables from the market, the other family members will reflect on their quality by making observations such as: fresh or stale, good or bad quality or inferior product, etc. These observations are perceptions of consumers based on the sensory attributes of the fruit or vegetable colour, appearance, touch, smell or taste. The quality characteristics of food that are acceptable to consumers are comprehended under the term “Food Quality. It includes external factors such as appearance (size, shape, colour, gloss, and consistency); internal factors (chemical, physical, microbiological) and characteristics/ specifications prescribed under the Government laws/standards. If consumer’s perceptions regarding quality of food are not positive he or she either will not purchase the material or will be paying less compared to when the consumer has positive perception about the quality. The relationship between quality, profitability and market share has been well established. In the quest of quality, the dairy business is passing through revolutionary changes and the need for such changes has been very well realized. The leaders have initiated the process of setting vision and are working hard to provide the basic infrastructure with necessary resources. This has become a point of vital importance as the nation has now captured the first rank in milk production globally and is now ready and set to march ahead in the global race for dairy products market. Our country has great potential to export the dairy products such as cheese particularly Mozzarella, Feta, and indigenous products such as ghee, khoa, chhana, paneer, and array of sweets. Food items or dairy products to be traded in the international markets should be manufactured in accordance with global accepted norms and standards. In order to improve the quality of milk and milk products the Government of India is focusing on “Clean Milk Production”. As a dairy technologists and entrepreneurs, we must ensure production of quality products.