eChapters

Genetically modified organisms (GMOs) can be defined as organisms in which the genetic material (DNA) has been altered in a way that does not occur naturally. The technology is often called “modern biotechnology” or “gene technology”, sometimes also “recombinant DNA technology” or “genetic engineering”. It allows selected individual genes to be transferred from one organism into another, also between non-related species. Genetically modified (GM) foods are foods derived from genetically modified animals and marines. Genetically modified animals and marines are those in which specific changes introduced into their DNA by genetic engineering using a process of either Cisgenesis or Transgenesis. These techniques are much more precise than mutagenesis where animals and marines are exposed to radiation or chemicals to create a non-specific but stable change. Other techniques by which food animals can be modified are selective breeding and somaclonal variation. By this means desired quality of meat, egg and other animal products can be produced. But it is a common thinking that foods derived from genetically modified animals and marines are far from safe. They are likely to be contaminated by potent vaccines, immune regulators and growth hormones, as well as nucleic acids, viruses and bacteria that have the potential to create pathogens and to trigger cancer.

Organic meat food products are choice products for health conscious people. These are the products produced mainly in most natural way without using fertilizers, pesticides and growth regulators in their feed and fodders. In addition, meat animals are also reared without growth hormones, antibiotics drugs etc. and grazing of the animals is a prerequisite in organic farming system.

The term organic farming was first time used by Lord Northbourne. The term organic farming was derived from his concept of “the farm as organism”. It is a holistic, ecologically balanced approach to farming. In 1991, the European Commission formulated the first government system to regulate organic labelling. In India, standards for organic agriculture were announced in May 2001 and the National Programme on Organic Production (NPOP) is administered under the Ministry of Commerce. The concept of organic meat food products has been emphasized now a day due to animal welfare point of view, consumer’s conscious ness, less residue level of chemicals, antibiotics and drugs, Bovine spongiform encephalopathy (BSE), Foot and mouth disease (FMD), genetically modified food etc.

Organic meat food products as a whole are dependent on the life stages of the livestock like its origin, feeding, housing, health, breeding, transportation and slaughter. The other factors accounting for organic foods are its production, harvesting, preservation and processing. Inspite of low growth rate of organic red meat globally, growth in dairy, egg and poultry is increasing day by day. At present 1.2 million hectares (0.6%) of Indian land is producing organic products (Willer and Kelcher, 2011).

Meat and meat products industry is a sunrise industry in India having huge potential for upliftment of agricultural economy. India is the second largest food producer in world but the contribution of meat industry is still confined to localized handlers. So to uplift industry basic infrastructure, food chains, food security and safety along with standards and laws formulation and their implementations is today’s need. Standards are carefully drawn specifications with respect to a food product. These standards are mainly of three types i.e. government, trade and research standards. Government standards are formulated by the government of India or state government and also have the power to implement these standards while trade standards are implied by the individual company. Research standards are formulated on the basis of comparative study of the products by the researchers. Laws are the legislations enforced by the organisations either government or by autonomous bodies made under the constitutional acts of the country. At present numerous standards and laws are in existence in individual country or at international level. The need is to harmonize them as per the industry and trade requirement.

Domestic Organizations Involved in Standards and Laws Formulation

For the formulation, enforcement and control of standards and legislations at domestic level various organizations are of prime value. Some of these are:

Eggs are considered as Nature’s original functional food because they are abundant source of nutrients like vitamins and minerals. It contains valuable nutrients from the high-quality protein to significant levels of beneficial vitamins, antioxidants and other healthful compounds. The protein of eggs is considered as highest quality protein as compared to other animal protein sources which is readily available and most inexpensive. Eggs are good source of all well balanced nutrients for persons of all age groups. Egg is a unique combination nutrient like it is rich in protein and low in calorie. The nutrients concentration in eggs is dependent on breed, strain, species, feed, age, season, storage and processing methods.

The nutritional value of eggs lies chiefly in their proteins of good biological value; an average-sized egg (60 g) provides approximately 7 g of proteins. These proteins are rich in essential amino acids with a very good balance between these amino acids. So the egg protein can be regarded as a reference protein. On comparison we can say that 2 eggs provide as much protein as 100 g of meat or 100 g of fish. The energy value for an average egg (60 g) is approximately 376 Kj (90 kcal). The lipid content is 7 g, most of these lipids being contained in the yolk. Among the total fatty acids 2/3^rd of these are unsaturated. Egg also contains 180 mg of cholesterol and rich in vitamins (A, D, E) and trace elements (iron and zinc).

Sensory evaluation is a scientific method of evaluating foods including meat products that applies principles of experimental design and statistical analysis through the use of human senses like sight, smell, taste, touch and hearing. It is also called organoleptic evaluation in which we measure, analyse and interpret reactions to those characteristics of materials as they are perceived by the human senses. These attributes can be perceived well by the human sense organs as compared to instruments available for this purpose. It is a fact that no single instrument is able to assess all the attributes of meat products. With the help of these instruments we can very well evaluate the single quality attribute of meat product i.e. shear force instrument or penetrometer is good for knowing the texture and refractometer is for colour interpretation.

Physico-chemical and microbiological quality of meat and aquatic food and food products gives its overall safety and quality status as a food. The physico-chemical and microbiological qualities of raw material have great importance on the product development. It also affects the shelf life of the raw material as well as final product.

Fresh meat is a type of meat which has not been subjected to any processing whereas raw meat is a fresh meat which has undergone freezing. The qualities of fresh meat are important as far as merchandiser, purchaser and consumers are concerned and it is also important for adaptability in further processing. The important quality parameters of fresh meat are:

Formulation of meat and sea food products requires various ingredients which are commonly known as food additives. Food additives are those non-meat ingredients which are used to enhance colour, flavour, aroma and texture of the meat and sea food products. These food products can fulfil the demand of modern consumers. As per the definition of Food and Drug Administration (FDA) food additives are those substance which are used to provide a technical effect in foods. The use of food additives has become more prominent in recent years, due to the increased production of prepared, processed, and convenience foods. Additives are used for flavour and appeal, food preparation and processing, freshness, and safety. These additives can be classified as curing ingredients, extenders and binders, flavour enhancers and other additives. For the formulation of different products both raw materials and ingredients should be of food grade and sound hygienic strength. In the starting of this chapter we will discuss about ingredients used then the specific formulations will be discussed for better understanding of meat and sea food processing.

Curing Ingredients

Curing agents such as salt, phosphate, sugars, nitrite and nitrate, sodium ascorbate and erythorbate etc. have traditionally been used in various meat formulations from long back. The details of these ingredients have already been discussed in chapter-8 of this book. So we will try to discuss other ingredients which are relevant for meat and sea food products other than these ingredients. Cure accelerators such as ascorbates and erythorbates are used to speed the curing process. They also stabilize the colour of the final product. The examples are ascorbic acid, erythorbic acid, sodium erythorbate, citric acid, sodium citrate, sodium acid pyrophosphate, glucono delta lactone (GDL) etc. Glucono-delta-lactone (GDL) acts as a curing accelerator in meat and meat products. It is permissible up to 1% in sausages and up to this level it lowers the pH about 0.5 thus inhibits the growth of spoilage micro-organisms. GDL also facilitate the cured colour development.

Food packaging is an essential technique for preserving food quality and minimizing food wastage. It is a scientific technique of containing food against physical, chemical and microbiological contaminants. In addition package also display the product in most appropriate manner and provide product information to the consumers while at the same time allowing convenient handling and efficient distribution. The packaging of meat and meat products are particularly important because meat is highly nutritious food and provides good medium for the growth of micro-organisms. Meat and meat products are also susceptible to bacterial growth due to their high water activity. Exposure of meat and meat products on atmospheric temperature and sunlight leads to various types of deteriorative changes. For example when cut meat surfaces exposed to ambient air provide excellent breeding grounds for most bacteria. Minced meat is even more at risk due to the large exposed surface area. Packaging provides protection of food against external and internal factors but once food gets deteriorated it can not be controlled by packaging. For this reason rigorous hygiene in all processing and pre-packaging steps is vital for packaging of perishable food items like meat and meat products.

Meat processing is the set of methods and techniques used to bring substantial chemical and physical changes in the natural state of meat. These are the methods which are used for making meat and their products attractive, nutritious and marketable as well as for the prolongation of shelf-life. In processing techniques, grinding, chopping, addition of seasoning, alteration techniques for colour, heat treatments etc. are included but cutting, trimming and deboning are not included in processing operations.

History

Meat processing dates back to the prehistoric ages and probably the first processed meat product was sundried meat. Lator it turns to burning of meat over wood fire while salting and smoking of meat was practiced first time in the time of Homer, 850 B.C. In 63B.C.-14 A.D. at the reign of Augustus honey was tried for preservation of meat. Lator various types of cooking such as roasting, smoking, steaming and oven baking came in existance. Salt-preservation was especially common for foods including meat and meat products for warrior and sailor’s diets, until the introduction of canning methods.

Modern food processing technology in the 19th and 20th century was largely developed to serve military needs. In 1809 Nicolus Appert invented a vacuum bottling technique that would supply food for French troops and this contributed to the development of tinning and then canning by Peter Durand in 1810. Although initially expensive and somewhat hazardous due to the lead used in cans. Canned goods would later become a staple around the world. Pasturization discovered by Louis Pasteur in 1862 was a significant advance in ensuring the micro-biological safety of food. In 20^th century, food processing advances with the development of spray drying, freeze drying and the introduction of artificial sweeteners, colouring agents and preservatives such as sodium benzoate. In late 20^th century ready to eat meat food products were introduced to cater the need of consumers.

Ageing of meat is also known as conditioning or tenderising or ripening or maturing and sometime resolution of rigor. It is a process of holding unprocessed meat above freezing point under controlled conditions. By this process we can make muscle soft and pliable thus meat becomes tender. When we keep the meat above freezing point at temperature between 0-3ºC then all those changes occurs which are normally occurs at higher temperature i.e. atmospheric oxidation and enzymatic action of fat, bacterial action etc. When this temperature range becomes below freezing point then it inhibits completely the enzymatic action in the muscles. Ageing is required for marked increase in flavour, juiciness and tenderness of meat. In this process action of enzymes in meat plays key role while bacterial action is not of any importance. Meat tenderness and taste are definitely improved if carcasses or vacuum packed cuts are conditioned after slaughter but paradoxically beef is quite tender just two hours after slaughter and several days of conditioning are required to recover this degree of tenderness.

During the contraction of muscles, thick and thin filaments sliding to each other and decreases the length of sarcomeres. In turn, this decreases the length of fibrils, fibres and the whole muscle. If these muscles remain in contracted length when rigor develops, it causes massive overlap of thick and thin filaments leading to severe meat toughness. It is also necessary to avoid the cooling of meat too rapidly after slaughter, otherwise it cold-shortens and gets tough. If we avoid cold-shortening of muscles during conditioning, it will increase meat tenderness. But with too much conditioning, weight loss, surface spoilage and the cost of refrigerated storage increases.

Ageing of carcasses with little or no fat cover is not recommended by meat specialists. Because these carcasses loose moisture rapidly, loose weight excessively and discolour the meat surface rapidly. In addition, lean meat is also susceptible to deterioration through microbial growth, slime formation by bacteria and mould growth etc. Ageing is important for beef and buffalo meat while pork and lamb do not require ageing because they are slaughtered in the age where they are young and inherently tender. Additionally, the unsaturated fats found in pork fat oxidize during ageing causes rancidity and off flavour. Veal has very little protective fat covering and is high in moisture; thus it does not lend itself to ageing.

Preservation of foods including meat and aquatic foods is a creation of conditions for the food articles in such a way to stop or greatly slow down the activities of micro-organisms, chemical and enzymatic reactions and physical forces to prevent the meat and aquatic foods from spoilage while maintaining its nutritional value and sensory attributes.

Significance of Meat Preservation

1. Meat and aquatic foods are perishable food items and are very prone to spoilage and rancidity development due to high nutrients, moisture and neutral pH.
2. Once meat and aquatic foods is exposed to microbial contamination, chemical and enzymatic reactions then it will be very difficult to attain asepsis.
3. To enhance the keeping quality of meat and aquatic foods so that it will be available for further processing.
4. It protects meat and aquatic foods from shrinkage, sweeting and other physical forces.
5. To protect human health by providing the wholesome meat and aquatic foods to the consumers.
6. By this way we can minimize utilization of energy in processing of meat and aquatic foods.

Fraudulent substitution of meat is the adulteration or mixing of the inferior or cheaper quality meat into superior quality meat. The first case of fraudulent substitution was recorded in thirteenth century A.D. at Florence in Italy. A common fraud in the meat industry in which uninspected meat is substituted for meat that has undergone inspection and been branded as satisfactory. The other frauds are the substitution of meat of another species, e.g. horse for beef especially in Britain and Ireland, beef in kangaroo meat in Australia, cat for chicken or rabbit, goat meat for mutton, mutton for venison, dog meat and cat meat for chevon in other countries including India. As per an estimate about 25-30% of meat sold in India is adulterated. These practices are more common in comminuted meat products. These illegal practices are punishable under PFA act 1955. The choice of method to be applied is depend on the need or condition of meat recovered.

Meat is an animal flesh that is used as food. Most often, this means the skeletal muscle and associated fat but it may also describe other edible tissues such as organs, livers, skin, brains, bone marrow, kidneys or lungs. Meat is highly nutritious food because it contains protein, fat and carbohydrates in relative proportion, supply energy as required by the human body, posses ability to build or replace tissues and the substances present in meat are easily absorbed by the human body. Meat is also a good source of B-complex vitamins but fat soluble vitamins are low in meat. It is a good source of phosphorous, zinc and iron but low in calcium. Meat also contains significant amount of copper, sodium, potassium and magnesium but low in carbohydrate contents. Carbohydrate is found mainly in form of glycogen which disappears completely after completion of rigor mortis. In general lean red meat is particularly good source of protein, niacin, vitamin B6, vitamin B12, phosphorus, zinc and iron. About 100g of meat can provide more than 25% RDI of these nutrients. It also provides more than 10% RDI of riboflavin, pantothenic acid and selenium. Of the four meats, mutton is particularly nutrient-dense and the richest source of thiamine.

Conversion of muscle to meat is a complex process in which several physical and chemical changes takes place over a period of several hours or even days. The major changes which take place during this process include fall in muscle pH and temperature as well as muscle shortening which further leads to proteolysis or ageing. These changes during conversion of muscles to meat are variable and have great effect on meat quality (tenderness, juiciness, flavour, colour etc.) and also on certain processing characteristics like emulsification, binding properties and yield of the products. To know this complex process it is necessary to understand the process of energy production and metabolic pathway shifting in live animals.

Pre Slaughter

In the living animal, aerobic metabolism is used to obtain energy. The source of energy at this stage is either free fatty acids or blood glucose or muscle glycogen. In this process total 38 ATP molecules are produced from single glucose or glycogen molecule by the complex processes known as glycolysis, oxidative decarboxylation and oxidative phosphorylation. However, under stressful situations, anaerobic metabolism may be used and lactic acid is produced. Lactic acid is usually transported from the muscles to the liver, where it is re-synthesized into glucose and glycogen, or to the heart, where it is metabolized to carbon dioxide and water.

The word meat comes from the old english word mete, which referred to food in general. Most often this means the skeletal muscle and associated fat but it may also describe other edible tissues such as organs, livers, skin, brains, bone marrow, kidneys and lungs etc. In other words we can say meat is those animal tissues which are suitable for use as food by the man. It is composed of numerous types of tissues like muscle tissues, epithelial tissues and nervous tissues but the major component of meat is muscle. Particularly skeletal muscle is the principal source of muscle tissue in meat while smooth muscle contributes little to meat. The muscle and connective tissues are the major compositional components and contributes towards qualitative and quantitative characteristics of meat. Broadly muscle can be classified into striated and smooth muscles. Striated muscles have transverse band pattern as seen in skeletal and cardiac muscle. However, smooth muscles do not show such pattern and mainly found as a component of blood vessels.

In spite of big potential of the largest livestock population in the world, meat industry in India is still in nascent stage. It is a business of those who are not trained and very much literate. The industry is primarily based on the raw material that is not reared for meat purpose but serves the secondary role after passing their viable life in primary field. The industry is also facing problem of social prejudice and meat is taboo for certain communities. But scenario is now changing and people are coming forward to organise the sector. Now the society is accepting the facts that meat is an only source of cheap and nutritious food to million of people in India and the good source of animal protein for large segment of Indian population, particularly landless, small and marginal farmers.

India ranks fifth in the world meat production with the annual meat production of about 6.3 million tones which is 2.21% percent of world meat production. In the last two decades meat industry in India has grown @ 4.5% whereas, during the last five years, this segment has been growing very fast at the rate of 27% annually. It has a good future if given proper attention by the Government and Private Entrepreneurs. In total meat production, share of cattle is 17.34%, buffalo 23.3%, sheep 4.6%, goat 9.4%, pigs 5.3%, poultry 36.6% and others 3.4%. The share of various meat types in total Indian meat production accounts buffalo meat 1.5 million tones, beef 1.28 million tones, mutton 0.24 million tones, chevon 0.53 million tones, pork 0.50 million tones, chicken meat 2.20 million tones and duck meat 0.07 million tones. To produce the above quantities, the extraction or slaughter rates in cattle are about 7.9%, buffaloes 11.1%, sheep 47.9%, goat 37.9%, pigs 88.9% and poultry 73.6%. In the world total meat production Indian cattle meat shares 13.1%, buffalo meat 55.8%, mutton 5.7% and chevon 14.9%. However, India is having world’s 15.0% (210 million) cattle, 57.0 %( 111 million) buffaloes, 7.0 %( 74 million) sheep, 17.0 %( 154 million) goat and 1.5% pigs. Overall contribution of meat sector in total output of Livestock sector was Rs 25984 crores in the year 2004-2005.

‘Prunes’ is prepared from peach.

Arrak” liquor is prepared from date palm.

Hayane” variety of date palm suitable for juice making.

Kanji” is made from black carrot.

Kirschwascer” a wine prepared from cherry.

Shahi” variety of Litchi suitable for canning.

New Technique of Food Preservation

1. High Pressure Processing (HPP)

High Pressure Processing (HPP) is a method of food processing where food is subjected to elevated pressures (up to 87,000 pounds per square inch or approximately 6,000 atmospheres), with or without the addition of heat, to achieve microbial inactivation or to alter the food attributes in order to achieve consumer-desired qualities. Pressure inactivates most vegetative bacteria at pressures above 60,000 pounds per square inch. HPP retains food quality, maintains natural freshness, and extends microbiological shelf life. The process is also known as high hydrostatic pressure processing (HHP) and ultra high-pressure processing (UHP).

Quality Standards and Laws

Quality is how well a product or service satisfies the needs of the customer. This includes all aspects related to the needs of the customer such as quality specifications, safetgy, delivery method or date, price etc. Quality can be interpreted in several ways as conformance to the standards, meeting customers’ preference/ satisfaction for desired quality attributes, degree of excellence and zero defect products etc. Because of education and consequent greater understanding of implications of poor quality commodities in recent years, consumers have become quality conscious and this fact is also applicable to food and food products. In order to strengthen competitiveness, quality must be incorporated throughout the value added chains right from the harvesting, handling, manufacturing, processing, packaging, storage, marketing and distribution stages, especially in the case of food and food products.

Food Safety and Standard Authority of India (FSSAI) has adopted the standards of Fruit Product Order (FPO).

Chutney

It is a product prepared by cooking the fruit pulp with added salt, sugar, spices, acetic acid and fruit to a suitable consistency so that it contains TSS not less than 50% and fruit part not less than 40% as per FSSAI specification. Sugar, salt, spices, acetic acid all act as partial preservatives. Preservatives may also be added in chutney for increasing its storability. Generally no artificial colour and flavor are required to be added.

Sauce

Sauce is a product similar to ketchup, prepared from pulps of tomato or other fruit/vegetable, having TSS not less than 15% and cooked to a suitable consistency with added sugar, salt, spices and vinegar. Sugar, salt, spices, acetic acid all act as partial preservatives. According to FSSAI specification fruit sauce should have minimum of 15% TSS and 1.2% acidity. Preservatives and colours may also be added for increasing of appearance and storability.

Preserves (Murabbas) are prepared from whole fruits and vegetables or their segments by addition of sugar followed by evaporation to a point where microbial spoilage cannot occur. The final soluble solids concentration is reached to about 70 per cent. The finished product can be stored with or without hermetic sealing and refrigeration.

Jam is prepared by boiling the fruit pulp with required quantity of sugar to thick consistency, firm enough to hold fruit tissues in position. It should contain not less than 68.5 per cent soluble solids. Jam may be made from a single fruit (apple, strawberry, banana, pineapple etc.) or from combination of two or more fruits. Jam contains 0.5-0.6% acid and invert sugar should not be more than 40%.

The preservation of food in common salt or in vinegar is known as pickling. It is one of the most ancient methods of preserving fruits and vegetables. Pickles are good appetizers and add to the palatability of a meal. They stimulate the flow of gastric juice and thus help in digestion. They are prepared with salt, vinegar, oil or with a mixture of salt, oil, spices and vinegar.

A dilute solution of acetic acid produced by a two-stage fermentation process in the first stage, fermentable sugars is converted into ethanol by the action of yeasts and in the second stage, bacteria of the genus Acetobacter oxidize the ethanol to acetic acid.

Vinegar is a liquid produced from the fermentation of ethanol in a process that yields its key ingredient, acetic acid. The acetic acid concentration ranges typically from 4 to 8 percent by volume for table vinegar (typically 5%) and higher concentrations for pickling (up to 18%). Natural vinegars also contain smaller amounts of tartaric acid, citric acid, and other acids.

Fruit juices which do not undergo alcoholic fermentation are termed as unfermented beverages. They include natural and sweetened juices, RTS, nectar, cordial, squash, crush, syrup, fruit juice concentrate and fruit juice powder. Barley waters and carbonated beverages are also included in this group.

Fermentation in food processing typically is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeasts, bacteria, or a combination thereof, under anaerobic conditions.

Freezing is one of the easiest and least time consuming methods of food preservation. The freezing process is a combination of the beneficial effects of low temperatures at which microorganisms cannot grow, chemical reactions are reduced, and cellular metabolic reactions are delayed.

Methods of Freezing

1. Sharp freezing (slew freezing)

In sharp freezing commodities are exposed at -15 to -29⁰C. It required 3-72 hrs. Here the thawed tissue cannot regain its original water content. The ice crystals formed are large and rupture the cells. The thawed tissue cannot regain its original H₂O content.

Removal of water from the food by non-conventional energy source like sunlight, wind, and a smoky fire. Drying (dehydrating) food is one of the oldest and easiest methods of food preservation.

Dehydration

Dehydration is the process of removing water or moisture from a food product under controlled condition like temperature, relative humidity, air flow, etc.

Principles of Drying and Dehydration

Drying removes the moisture from the food so that bacteria, yeasts and moulds cannot grow and spoil the food. It also slows down the action of enzymes, but does not inactivate them. Dried food items can be kept almost indefinitely, as long as they are not rehydrated.

Canning is a process of sealing food stuffs hermatically in containers and sterilizing them by heat for long storage is known as canning.

Principle of Canning

Destruction of spoilage organism within the sealed container by means of heat.

Selection of Fruit and Vegetable

For canning fruit should be ripe but firm and uniformity mature and vegetables except tomato should be tender.

Grading

Selected fruit and vegetable are graded according to size and colour to obtain uniform quality. This is done by hand or machines such as screw grader and roller grader.

Food additive is any chemical substance that is added to food during preparation or storage. A food additive either becomes a part of the food or affects its characteristics for achieving a particular effect. For instance, substances that are used to enhance the appearance, texture, or to keep qualities of a food are considered food additives.

Preservation means just protect the foods against the spoilage, but scientifically it may be defined as a science which deals with the process for prevention of decay or spoilage of the food is called preservation.

In other words, just controlling the physical, chemical or microbial changes in the foods is called preservation.

Physical Changes: Colour, flavour, texture and taste etc.

Chemical Changes: Carbohydrate, fats, proteins, vitamins and minerals.

Microbial Changes: Mould, yeasts and bacteria

Physiological disorders refer to non-parasitic or inanimate disease of fruit crops, or it is the breakdown of tissue that is not caused by either invasion by pathogens or by mechanical damage. They may develop in response to an adverse environment, especially temperature or to a nutritional deficiency during growth and development. Physiological disorder is broadly classified into two broad categories. They are:

Packaging is an important consideration in vegetable and fruit market. The use of properly designed containers for transporting and marketing of vegetables is significantly reduce losses and maintain their freshness succulence and quality for longer period. Packaging also provides protection from mechanical damage and undesirable physiological changes and pathological deterioration during storage, transportation and marketing.

Many vegetables are transported in gunny bags and bamboo baskets. Packaging material such as polythene films, paper boars, and boxes lived with polythene and other materials can effectively prolong the shelf life of vegetables. By using plastic films vegetables can be protected from dry air. Polythene packaging provides modified atmosphere and consequently reduces decay, softening, and loss of solids. The thickness and permeability to CO₂, O₂ and water vapour of films needs to be standardized for each vegetable.

Proper marketing of perishable commodities such as fruit and vegetables often requires some storage to balance day-to-day fluctuation between harvest and sale or for long term storage. Storage of horticulture produce is attempeted with a view to extend period of availability. Storage controls shelf life of produce by controlling rate of respiration, transpiration, ripening and biochemical changes all of which are responsible for shelf decomposition/deterioration of produce. Further, different types of storage have different attributes in minimizing microbial infection and thus add to better storability of produce.

It is a most deteriorating biological process of the harvested fruits and vegetables that leads to the oxidative breakdown of the complex material (carbohydrates or acids) of cell into simpler molecules (CO₂ & water) with production of energy. Respiration includes glycolysis metabolism, aerobic metabolism, anaerobic metabolism, trycarboxilic acid cycle and electron transport metabolism processes.

Ethylene (C₂H₄ also known as ethene) is a gaseous organic compound that is the simplest of the alkenes chemical structures (alkenes contain a carbon-carbon double bond). The hormone effects of ethylene on general plant growth were first noted in 1864 when leakage from gas street lighting systems caused stunting and deformation of nearby plants. In 1901 Neljubow identified the active component of the gas to be ethylene but it was not until 1934 that Gane identified that plants could synthesize ethylene and in 1935 Crocker proposed ethylene to be the hormone responsible for fruit ripening and senescence of vegetative tissues.

Ethylene play important role in many plant during development processes, including seed germination, vegetative growth, leaf abscission, flowering, senescence and fruit ripening. Ethylene also plays a role in response to water stress, chilling and mechanical injury.

Ripe

This word is derived from Saxon word ‘Ripi’, which means gather or reap. This is the condition of maximum edible quality attained by the fruit following harvest. Only fruit which becomes mature before harvest can become ripe.

Ripening

Ripening involves a series of changes occurring during early stages of senescence of fruits in which structure and composition of unripe fruit is so altered that it becomes acceptable to eat. Ripening is a complex physiological process resulting in softening, colouring, sweetening and increases in aroma compounds so that ripening fruits are ready to eat or process. The associated physiological or biochemical changes are increased rate of respiration and ethylene production, loss of chlorophyll and continued expansion of cells and conversion of complex metabolities into simple molecules.

Since time immemorial, spices have played a vital role in world food trade, due to their varied properties and applications. We primarily depend on spices for flavour and fragrance as well as colour, preservative, inherent therapeutic, medicinal and appetizing properties. The spices that India can offer in abundant quantities are pepper, ginger, turmeric, chili, cardamom, celery, fenugreek, fennel, cumin, dill, coriander, cinnamon, ajowan, cloves, nutmeg, mace etc.

Flowers are highly perishable unlike other horticultural or agricultural crops. Owing to poor keeping quality the post harvest losses in floriculture are significantly higher than any other sector. Although there has been significant increase in the area, production and productivity of flower crops in the last two decades, there is an urgent need to minimize the huge post harvest losses in terms of the value of the produce which are estimated to be 30-40 per cent of farm value. The post harvest behavior of flowers is an outcome of the physiological processes, occurring in leave, stem, flower bud, leafless peduncle or scape connecting bud to the stem. Some of these processes may act independently to affect the senescence and vase life of cut flowers but most of them are inter-related. The nature and extent of post harvest damage is typical for each crop or cultivar. The post harvest losses become important especially when dealing with the export of fresh flowers to distant and foreign market. Therefore, patient, soft and expert handling of flowers is of utmost importance after harvest.

Fruits and vegetables are living tissues subject to continuous change after harvest. Some changes are desirable from consumer point of view but most are not. Post-harvest changes in fresh fruit cannot be stopped, but these can be slowed down within certain limits to enhance the shelf life of fruits. The post-harvest handling plays an important role in extending the storage and marketable life of horticultural perishables.

Post Harvest Treat ment of Fruits and Vegetables Washing

It is useful in removing surface adhering material water. Mechanically, it is also accomplished by passing the fruits/vegetables through machine arranged with water tank equipped with rotating brush. In some produce washing improves appeal by facilitating removal of sap as case in mango, papaya, jackfruit, kronda, dirt in case of carrot, reddish, turnip, sugar beet, sweet potato, etc. and for removal of debris in case of banana. The water use for the purpose should be cleaned otherwise fungal and bacterial levels may build up. Disinfected treatment using ultraviolet light, ozone, chlorine (100 ppm), calcium hydroxide, etc. help to clean water for washing purpose.

Maturity

It is derived from Latin word ‘Maturus’ which means ripen. It is that stage of fruit development, which ensures attainment of maximum edible quality at the completion of ripening process.

Maturation

It is the developmental process by which the fruit attains maturity. It is the transient phase of development from near completion of physical growth to attainment of physiological maturity. There are different stages of maturation e.g. immature, mature, optimally mature, over mature.

Maturity Indices

The factors for determining the harvesting of horticulture commodities according to consumer purpose and type of commodity.

Maturity Indices is two type

Fruits and vegetables are important part of our dietary, which are rich source of nutrient (carbohydrates, protein, fat, vitamins, minerals, and dietary fiber). Carbohydrates, protein and fat are macronutrients, considered as energy sources. Vitamins and minerals are micro nutrient, play important role in body building. Fibers have several direct and indirect advantages. ICMR, New Delhi recommends 125g of leafy vegetables, 100g of root and tuber vegetables and 75g of other vegetables (total 300g/day) and 85g of fruits per capita every day for balance diet.

India is a second largest producer of fruits and vegetables after China. These share are 10% and 16% respectively in total world production. Horticulture crops occupy 23.548 million ha and production is estimated around 260.063 million tones. Total area of fruits, vegetable, plantation crops, spices, loose flower and aromatic plant are 7012, 9083, 3606, 3092, 218 and 537 thousand ha, respectively and production are 79400, 156445, 16388, 5786, 1421 and 622 thousand tones, respectively with productivity are11.32, 17.22, 4.54, 1.87, 6.59, 1.19 thousand tones per ha, respectively (2012-2013). The total productions of cut flowers are 74305 Lakh stem (2012-2013). The annual horticulture export volume is 2733145 metric tonnes (2010-2011) with total exported value of Rs 696461 lakh. In terms of volume, fresh fruits & vegetables comprised about 76 % of exported horticulture produce followed by processed fruits & vegetables (23 %) and floriculture & seeds (1%). After that losses found 20-30 % in fruit and 30-40 % in vegetable while harvesting to consumption in India. It’s due to the perishable nature of horticulture commodity, non availability of appropriate post harvest infrastructure transportation, inadequacy of the market or lack of processing.

India is a major horticulture producer, even though processing is less than 2 %. This is very low as compare to 80 % of Malaysia, 78 % of Philippine, 70 % of Brazil and 30 % of Thailand. The most of developed country 40-60 % fruits and vegetables utilize in processing.

Proper handling, packaging, transportation and storage reduce the post harvest losses of fruits and vegetables. For every one percent reduction in loss will save 5 million tons of fruit and vegetable per year. Processing and preservation technology helps to save excess fruit and vegetable during the glut season. The technology has become a necessity to improve the food safety and strengthen nations food security. The technology helps to boost export of agricultural commodities in the form of preserved and value added products.

The dairy processing industry in India deals mainly with the fluid milk and/or short shelf life products, despite India being the largest producer of milk in the world, with an output bordering the 110 million ton mark. This feature offers immense potential in the area of R&D in dairy processing in terms of value addition. The potential gains are many, including higher returns for producers and advantages in terms of health, therapeutic, nutritional and/or gastronomy for the consumers. However, the Indian Dairy Industry can amass possible benefits by being a global contender in trade only when its products are at par with those available in the rest of the world in terms of price and quality. It is evident from the post-WTO scenario that for sustainability, Indian dairy industry will need to maintain wholehearted commitment to quality management right from the farm to the consumer, shedding its inhibitions and resistance to changes.

9.1. WTO Agreements and Food Industry

The General Agreement on Tariffs and Trade (GATT) was formed in 1947 and lasted until 1994, when it was replaced by the World Trade Organization (WTO) in 1995. The WTO is the only global international organization dealing with the rules of trade between nations. It provides a forum for negotiating agreements aimed at reducing obstacles to international trade and ensuring fair deal for all, thus contributing to economic growth and development. Currently, there are 16 agreements to which all WTO members are parties and two agreements to which only some WTO members are parties. WTO currently has 153 members, of which 117 are developing countries or separate customs territories. The Head Quarters of WTO is at Geneva (Switzerland) and the official languages are English, French and Spanish.

India has achieved a commendable position of being the highest milk producing country in the world. Nearly 110 million tons of milk per annum is contributed by small and marginal farmers having 2-3 milch animals which are scattered in lakhs of villages across the length and breath of India. The poor socio-economic conditions are serious constraints in producing raw milk of good quality. The quality of milk is further deteriorated during subsequent handling and transportation. Milk being a product of biological origin, is extremely vulnerable to attack by microbes. It is also a good vehicle for additives and adulterants without any apparent changes in its appearance. Thus, milk is susceptible to several post-secretion changes, some natural and some man-made.

Indian dairy industry faces a mammoth task to meet the world quality standards, particularly in the present context of globalization and increasing quality conscious consumers. In view of the highly perishable nature of milk soon after it is secreted, it is important to monitor its quality by having a firmly installed quality assurance programme along the entire production-to-supply chain. This can be possible with application of sensitive, accurate and rapid methodologies as a tool in quality assurance programmes.

Quality comprises of several attributes ranging from physical, chemical, technological and bacteriological through nutritional to aesthetic. All dairy plants have a quality assurance laboratory (Fig. 8.1) and usually follow chemical quality control with the intention of payments to contractors/producers, processing of milk and meeting mandatory requirements for end products. Quality is judged both by objective and subjective tests.

Cleaning and sanitisation are the two processes employed in dairy industry to ensure hygiene and product safety. The safety of milk and milk products is a very important aspect and every attempt should be made, during processing, to minimize contamination through handling and processing equipments. The accumulated dried milk solids (milk stones) consist largely of calcium phosphate, milk proteins (precipitated, coagulated and baked on by heat) and insoluble calcium salts from water and washing detergents. The surface can also contain biofilms, which are formed by the incorporation of bacteria into the accumulated inorganic and organic materials that attach to most surfaces. With time and in the presence of nutrients, a biofilm and the bacteria within the biofilm will grow and become strongly attached to the surface. The removal of dairy soil, milk stones as well biofilms is the prime objective of the cleaning process. International Dairy Federation (IDF) defines a clean surface as one which is free from residual film or soil that will not contaminate the food products coming in contact with it.

While cleaning refers to the removal of soil from the surface of the equipment, sanitisation implies destruction of all pathogenic and almost all non-pathogenic organisms. Cleaning and sanitisation are complimentary processes. Either of the processes alone will not achieve the desired result, which is to leave the surface as free as possible from soil and viable organisms. In actual practice cleaning and sanitisation overlap to some extent, as during cleaning a high proportion of bacteria are destroyed and others get removed in the detergent solution. Inadequate or faulty cleaning and sanitisation can have serious consequences, as milk is a prefect nutrient in which bacteria can multiply. A thorough understanding of the cleaning methods is, therefore, necessary for economic production of high quality food products.

Packaging is a tool that is used to contain the product, protect the product from environmental hazards and help in marketing the product. Examples of ideal natural packaging systems are that of a banana, orange, coconut and egg, where the packaging is provided by nature. The major step forward in the food processing arena has been the ability to protect and preserve products with packaging and hence ensuring the availability of fresh and processed products out of season and over long distances in various forms. Milk is a highly perishable product and is not uniformly available round the year to the whole country due to geographical and genetic variations. If dairy products are to be available all the year round the country, irrespective of the season and area, it must be presented in packages that are convenient to purchase and use.

Packaging has additional responsibilities of providing convenience, safety and facilitating, besides handling, storage and distribution of products. It should prevent spoilage of food by microbial or insect attack. It also preserves the quality and nutritive value of many foods by the exclusion of oxygen and the control of moisture loss or gain. It increases the shelf-life and ensures longer availability and contributes to the product image through structural and graphic design. Product information is also given out through the medium of labeling, which acts as a tool for marketing and advertising.

Milk, as secreted in the udder of a healthy animal is practically sterile, but during its transit to the processing plant, becomes heavily contaminated with a variety of micro-organisms. These may be responsible for spoilage of milk or for causing diseases in animals and human beings. It thus becomes imperative that adequate heat treatment is given to milk to destroy these micro-organisms, thus increasing the shelf-life of milk as well as making it safe. Varied heat treatments offer the potential of producing different kinds of processed milk to satisfy the needs of the consumer. To cater to the ever-increasing demand of consumers, several varieties of processed milk are available in the market, some of which are discussed below.

5.1. Pasteurised Milk

Pasteurisation was named after the renowned French scientist Louis Pasteur, who discovered that spoilage organisms could be inactivated in wine by applying heat at temperatures below its boiling point. The process was later applied to milk and remains the most important operation in the processing of milk.

It is the process by which every particle of milk is heated to such temperature-time combinations (usually to 63°C for not less than 30 minutes or to 72°C for not less than 15 seconds) and promptly cooled to 4°C or below so as to destroy any harmful bacteria that may be present without affecting flavour and food value. Pasteurisation does not involve the use of any additives. Apart from making milk safe to drink, pasteurisation increases the length of time it can be kept before it spoils. The nutrient losses due to pasteurisation are so small, that they are considered insignificant.

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