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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 13^th 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.

SYNOPSIS

Vegetables are essential for well-balanced diet since they supply phytonutriceuticals. About 3 billion people in the world are malnourished due to imbalanced diets. Regular consumption of a vegetable rich diet has undeniable effects on health since they have been strongly associated with improvement of gastrointestinal health, good vision, and reduced risk of heart disease, stroke, chronic diseases such as diabetes, and some forms of cancer.

Introduction

Fermentation is an alluring procedure of biochemical adjustment of essential nourishment microorganisms and their enzymes accomplish by lattice. Fermentation is a utilized to upgrade bio-accessibility and bioavailability of supplements from various crops and improves organoleptic properties (e.g., appearance, generation of sour taste and new aroma compounds, and textural changes such as consistency or viscosity) just as increase the shelf life of realistic usability. It makes foodstuff safe not just hindering the growth of pathogenic microorganisms because of antimicrobial growth of lactic acid and it also detoxifies aflatoxin. With these advantages, fermentation is a successful method to reduce the risk of mineral deficiency among population, particularly in developing nations where unrefined cereal or pulses are profoundly consumed. Tragically, it is additionally connected with multiplication of microorganisms, for ex., yeast and molds caused food safety concerns, (Omemu et al; 2011), decrease in provitamin A and antioxidant (Ortiz et al; 2017), carotenoids, just as loss of nutrients and minerals (Hotz & Gibson, 2007).

Fermentation is a minimum cost-efficient procedure for production and preservation of nutrient, therefore fermented food is an important piece of the eating regimen in numerous of the world. In the nineteenth century the scientific study of microbiology began, and just because, the scientific procedure of fermentation was comprehended. several classifications have been utilized to sort the assorted exhibit of the fermented nourishment produced dependent on various microorganisms, and food types, and kinds of fermentation included.

The microorganisms associated with fermentation process fall into three classes: bacteria, yeast, and molds. Yeasts are the principal microorganisms for the fermentation of breads, whereas molds is mainly used in processing of cheese and legumes. Bacteria is included only of the fermentation of cereal product. cereal and tuber fermentation are a lactic and acetic acid producing bacteria. yeast is a piece of mix microbial fermentation by bacteria in weaning food; all the more frequently, be that as it may, alcoholic fermentation of yeast may not totally alluring. Four genera of lactic acid producing bacteria are recognized as overwhelming cereal fermentation to be specific, Lactobacillus, Leuconostoc, Pediococcus, and Lactococcus spp. all of which require carbohydrate for the energy. Lactic acid and other natural acids produced from hexoses bring down the pH from about 6.5 to about 3.6. In the event that the pH is beneath 4.0, fermented product retard the growth of pathogens and along these lines ensure fermented items.

    1.    Microbial Risk Assessment (MRA) can be considered a tool for use in the management of the risks posed by food borne pathogens and in the elaboration of standards for food in international trade.

    2.    MRA comprises risk assessments of particular pathogen - commodity combinations

    3.    According to codex alimentarious commission (CAC) microbial risk assessment is defined as a scientifically based process consisting of 4 components.

        ·    Hazard identification
        ·    Exposure assessment
        ·    Hazard characterization
        ·    Risk characterization

India has emerged as the largest producer of milk in the World. This has boosted the confidence of producers, planners, dairy entrepreneurs and scientist alike. India has poised to play a major role in global dairy market in coming decade. The rapid growth of science and technology has positive impact on our life style and with strong trend of urbanization several demographic changes are likely to occur. There going to be ever increasing demand on the role of milk and milk products for human health. Accordingly, the demand for higher standards of milk products in terms of hygiene and safety of dairy products is to be followed. The competitiveness for the export of milk products among different dairy industry has increased in recent times due to GATT agreement. The biggest challenge before Indian dairy industry is the quality and safety of milk products indented for human consumption. Legal standards are made to have control over quality of food offered for sale and to safe guard the consumer form health hazards. It is therefore, imperative to determine different parameters that define product quality and safety. The purpose is to ensure production and distribution of products within well defined and accepted standards. This chapter deals with various parameters of product testing in order to maintain requisite prescribed standards.

1. Introduction

Fruits and vegetables have been an integral part of man’s diet from immemorial times. Fruits are the portions of plants that bear seeds, while vegetables are the edible components of a plant, including the leaves, stalks, roots, tubers, bulbs, flowers and seeds. These can be eaten raw or cooked. Fruits and vegetables can be preserved for short-term intervals under refrigeration, with or without receiving a minimal treatment like slicing, chopping, shredding or peeling. Fresh produce may also be irradiated or packaged in controlled or modified atmosphere in films for short-term storage. Long-term preservation includes canning, juicing, drying and addition of preservatives. Food contamination with hazardous biological agents remains a worldwide challenge in food safety and nutrition (Kenny 2002; Schlundt 2002; Tauxe et al 1997). Microorganisms form part of the epiphytic flora of fruits and vegetables and many will be present at the time of consumption. Production practices, growth conditions and the location of the edible part during growth (soil, soil surface, aerial part) will in combination with intrinsic, extrinsic, harvesting and processing factors affect their microbial status at the time of consumption. Man-made sources may be directly from farm laborers and from the equipment used for harvesting or storage. The types of microorganisms on fruits and vegetables would also vary with the orchards, vineyards or growing fields. The resident microflora normally subsists on the slight traces of carbohydrates, proteins and inorganic salts that dissolve in the water exuding from or condensing on the epidermis of the host. The numbers of bacteria present will vary depending on seasonal and climatic variation and may range from 104 to 108 per gram. The inner tissues of fruits and vegetables are usually regarded as sterile (Lund 1992). However bacteria can be present in low numbers in the insides of the fruits and vegetables as a result of the uptake of water through certain irrigation or washing procedures.

1. Multiple Choice Questions

A. Mixing and Homogenization

1. I.ntroduction to Mixing and Homogenization

In the food industry, mixing and homogenization are fundamental procedures that are essential to the production of a wide range of food items. To produce the desired qualities and final result with uniformity and consistency, various ingredients are blended. Ensuring product quality, stability, and customer happiness are contingent upon these processes.

Importance of Mixing and Homogenization

Mixing and homogenization are paramount for several reason

Milk, on reception at the dairy factory is subjected to various unit operations on its way to product manufacture. Processing is applied as a means to convert liquid milk into products or to render the milk (and products) safe from harmful organisms. The basic processing operations to which milk is subjected at processing units have been described in this chapter. The common processing operations employed are depicted in Fig. 4.1. Several of these operations are routine compulsory processes common to all dairies, while certain others are undertaken for specialized purposes in some dairies.

4.1. Filtration and Clarification

At the time of milking various foreign materials such as dirt, feed, manure, dandruff, hair, flies, dust particles, worn out cells, cell debris and many other undesirable substances may find their way into milk. The process of removal of this extraneous matter (solid particles of higher density than that of milk) is called filtration or clarification. This can be achieved either by simple filtration through specially woven filter cloth or continuous process of centrifugal clarification that helps

Key Facts
        
Agricultural food
    
·    There are multiple pathways through which climate-related factors may impact food contamination and food safety, food quality, foodborne diseases including changes in temperature and precipitation patterns, increased frequency and intensity of extreme weather events, ocean warming and acidification and changes in the transport pathways of complex contaminants.
    
·    All or most foodborne pathogens and their associated diseases are linked to changing environmental conditions, the notable of which are campylobacteriosis, salmonellosis and vibriosis.
    
·    An estimated 30% of reported cases of salmonellosis across much of continental Europe have been attributed to warm temperatures, especially when they exceed a threshold of 6°C above average. Likewise both in Australia and Canada a positive correlation was found between increasing temperature and incidence of salmonellosis.
    
·    Zoonosis such as Rift Valley Fever (RVF), West Nile Fever, tick-borne diseases and non-zoonotic animal diseases such as Blue tongue, African horse sickness, African swine fever are examples of animal diseases whose distribution is expected to be strongly influenced by climate change and variability.
    
·    Mycotoxin is a toxic secondary metabolite produced by filamentous fungi, commonly known as moulds and may contaminate agricultural commodities (food) by growing on them both before and after harvest, whenever the humidity and temperature are permissive. The most prominent mycotoxins are aflatoxins, deoxynivalenol, zearalenone, ochratoxin-A, fumonisin, and patulin.
    
·    The humans ingestion of mycotoxins occur through consumption of the mycotoxin contaminated plant-based foods, such as grains, maize, barley, rice, coffee, nuts and their residues, and metabolites in animal-derived foods, for example aflatoxin M1 (AFM1) in milk and meat products. In addition, mycotoxins may occur in beer and wine.

Jay et al., (1995) and Joerger et al., (2003) have written the role of bacteriocins as an alternate to antibiotics. Bacteria produce bacteriocins which are proteinaceous in nature or peptidic toxins. These inhibit the growth of similar or closely related bacterial strain(s). There are different types of bacteriocins which are classified based on the producing strain, common resistance mechanisms and mechanism of killing. Ahmad et al., (2013) have isolated antifungal compound for food preservation. Martin et al., (2018) and Batish et al., (1997) found antibacterial compounds from fungus. Mahboubi et al., (2019) studied the potential of Zataria in IBS. There are bacteriocins from gram-positive bacteria known as the colicins, the microcins and the bacteriocins from Archaea (Cascales et al., 2007). The bacteriocins from E. coli are called colicins (formerly called ‘colicines,’ meaning ‘coli killers’). These have been studied widely. Earlier called colicin V and is now known as microcin V. It is very small and is produced and secreted in a different manner than the classic colicins. Adrienne et al., (2016) have studied the colicin resistance.

5.1 Present Status

Export of pomegranate has decreased in quantity from 36,027.43 tons in 2012-13 to 20,997.02 tons in 2014-15, whereas in value term it show an increase trend during the same period. There is tremendous potential for exports of pomegranate from India and it is fact that India is largest producer of pomegranates in the world. Moreover, India produces finest edible quality of pomegranates which are available almost throughout the year. The major Markets of India’s pomegranate during the year 2014-15 were UAE, Nepal, Saudi Arabia, Kuwait and Netherland.

Milk is a highly perishable commodity. The shelf life of raw milk is in hours. In order to harness its full potential for the well being of the humanity, it is essential to extend its shelf life not only in days but also in months and years. This can be achieved by judicious application of processing and preservation technologies.

Preservation is any purposeful treatment or processing of a food which prevents spoilage and extends the shelf life of raw material to a longer than its natural keeping quality.

During storage and distribution foods are exposed to a wide range of environmental conditions. Environmental factors such as temperature, humidity, oxygen and light can trigger several reactions that may lead to food deterioration. As a result foods may be altered to such an extent that they are either rejected by the consumer or are harmful to the person consuming them. It is, therefore, essential that the good knowledge of different reactions that cause food deterioration is gained prior to understanding the principles of food preservation.

The deterioration in foods may be caused either due to internal or external chemical or microbial reactions occurring in milk. The changes may be either latent to senses of consumer, or they may be discernible by the human senses. The consumer cannot perceive latent changes visually, olfactorily or otherwise, and laboratory measurements are the only method to detect them. Still the nutritional value of such materials may be seriously impaired. Such changes include fermentation, oxidation of lipids, loss of vitamins and changes in the contents and composition of nitrogenous substances.

Non-microbial changes in foods, perceptible to human senses, may often lead to serious deterioration noticeable to the average consumer. These include discolouration and changes in odor, taste and consistency. Microbial changes may result in alteration of original properties of milk making it unfit for further processing, deterioration in flavour quality, loss of nutrients and toxin production.

1.1. General Discussion of Milk

“The cow is the foster mother of the human race. From the days of the ancient Hindoo to this time have the thoughts of men turned to this kindly and beneficent creature as one of the chief sustaining forces of human life”.

William Dempster Hoard (1836-1918)
Former Governor, State of Wisconsin, USA (1889-1891)
Founder of Hoard’s Dairyman (1885)

The oldest written records of the human race are in Sanskrit and are preserved in India. At the time these records began, about 6,000 years ago, milk had already become an important article of food. In fact, so important was the cow to these early people of South and Central Asia that wealth was measured in numbers of cattle, and the cow was in time made a sacred animal and is still so considered in India.

According to the best authorities, the domestication of cattle must have occurred somewhere between 6,000 and 10,000 years ago. The cow was worshipped in Babylonia, and in Egypt about 20,000 B.C. Over fifty references to cows and milk are found in Old Testament and the Promised Land was described as “a land flowing with milk and honey”.

Milk is the only food of the young mammal during the first period of its life. The substances in milk provide more energy and the building materials necessary for growth. Milk also contains antibodies which protect the young mammal against infection. A calf needs about 1000 litres of milk for growth, and that is the quantity which the primitive cow produces for each calf. There has been an enormous changes since man took the cow into his service. Selective breeding has resulted in dairy cows which yield more than 5,000 litres of milk per calf, i.e. five times as much as the primitive cow. Some cows can yield 10,000 litres or more.

Introduction

    1.    Food Science is the application of the physical, biological and behavioral science to the processing and marketing of foods (Margaret, 1968).

    2.    Technology can be defined as the science dealing with knowledge of doing things efficiently and effectively.

    3.    Food science helps us understand the theory example: what methods can best be used to store and preserve food to maintain quality and prevent spoilage.

    4.    Food technology demonstrates how the food is stored, preserved, processed and transported and has been responsible for development of new techniques for processing and preservation of food on a commercial scale and for packaging it in such a way that it can be sold conveniently.

    5.    Food science deals with the study of facts of the physical, chemical and biological sciences as they influence the processing and preservation of food.

    6.    Food technology deals with engineering and other scientific and technical problems involved in transforming edible raw materials and other ingredients into safe, nutritious and appetizing food products (Desrosier, 1977).

    7.    Food science is concerned with basic scientific facts about food, where as food technology concerned with the processing of raw materials into foods that meet human needs and wants.

    8.    Indian agriculture has undergone a sea change during the past half a century. Starting with the campaign for “grow more foods” in the forties, India reached self sufficiency during the eighties.

1. FOOD AND ITS SIGNIFICANCE

Food is the basic necessity of all the living world and the man is no exception to this. The basic purpose of food is to provide energy for the routine body functions and protect the body from various diseases. Life cannot be sustained without adequate nourishment for a healthy and active life, diets should therefore, be planned and consumed on sound nutritional principles (Fig. 1). For want of nutritious foods, consequence is the prevalence of malnutrition. There are several diseases that are related with deficiency of nutrition food, if not consumed. Such diseases include Kwashiorkor that can develop in children consuming insufficient protein even if total calories are sufficient. Marasmus is often due to the cessation of breast feeding and the attempt to replace it with foods, inadequate in protein such as rice broth. Other nutritional diseases still found particularly in the developing world are childhood blindness (vitamin A deficiency), rickets (vitamin D deficiency), beri-beri and infantile beri-beri (inadequate thiamin intake), pellagra (inadequate niacin intake), anemia (iron deficiency), goiter (iodine deficiency), etc. To cope up with this, the diet needs to be supplemented with nutritious food components including fruits and vegetables to make it more suitable for the growth and development of body.

Out of different types of foods, the fruits and vegetables constitute an important component of the food. Horticultural crops occupy a prominent position both in the importance and production in the world. The temperate fruits and vegetables are an important part of the horticultural crops, in terms of production and role in human health. These crops assume all the more importance due to their antioxidant activity, and presence of minerals and vitamins. Both fresh and processed fruits and vegetable, their different products are consumed. They are also called as protective foods. Fruits and vegetables are major sources of important vitamins like B and C and minerals such as Ca, Fe, P and K.

    1.    Wohler (1828) synthesized the first organic compound, urea from inorganic components.

    2.    Emil Fischer (1894) demonstrated the specificity of enzymes and the lock and key relationship between enzyme and substrate.

    3.    Michaelis and Menten (1913) developed kinetic theory of enzyme action

    4.    Watson and Crick (1953) Proposed the double-helical model for DNA structure

    5.    Ingo potrykus (1999) Golden rice- rich in b-carotene.

    6.    Glyoxysomes : Glyoxysomes are temporary in that they occur during transient periods in the life cycle of a plant such as in certain beans and nuts which store fats in their seeds as energy reserves. Glyoxysomes appear in the first few days after seed germination in endosperm cells and associate closely with lipid bodies. They disappear after the storage fats are broken down and converted into carbohydrate.

1. MATURITY INDICES

Maturity indices (right time of harvesting) are quality factors that give clues as to when a product should be harvested to allow marketing flexibility and ensure the attainment of minimum acceptable quality to the user. It also refers to the set of criteria used to determine the stage of maturity for harvesting the horticultural crops. Commodities harvested either pre-mature or too late are more susceptible to postharvest physiological disorders, diseases and have poor shelf life than harvested at right stage of maturity. The pickers/ handlers are trained in methods of identifying produce that is ready for harvest. However, optimum harvesting stages depends upon type of produce and their final use. Horticultural crops may be harvested at two main maturity levels i.e., physiological maturity and commercial or horticultural maturity. Therefore, the proper stage/maturity indices for harvesting of all horticultural crops should be identified for their implementation during harvesting. Horticultural maturity in relation to developmental stages of the plants is depicted in Fig 3.1.

Family: Acanthaceae

Flowering: October-December

Fruiting: January-February

Botanical description: The plant is a stout aquatic perennial herb growing up to 1-2 m high. The stems are erect, unbranched and hairy near swollen nodes. The leaves are sessile, linear- oblong, stalkless, 10-15 cm long, occur in whorls of 6 at each node on the stem. Straight, yellow, 4 cm long spines are present in the axil of each leaf. Flowers are purple in colour, occur in 4 pairs at each node and open in opposite pair.