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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.

Introduction

Development of improved crop varieties is vital for sustained increase in agriculture production and productivity. Timely supply of quality seed is equally significant since the contribution of quality seed alone is estimated to be 15-20 per cent to total crop production. Seed quality attains more significance in view of emerging biotic and abiotic stresses, issues related to quality and phytosanitary measures, competition in domestic and international markets and emerging food needs. Measures of seed legislation with respect to quantity and quality were initiated in the country by establishment of National Seed Corporation during 1963 under Ministry of Agriculture. The seed sector in India during the period was dominated by the Public sector. The National Seed Corporation was the Central Body to produce seeds of superior dwarf varieties in rice, wheat, and superior hybrids in maize, pearl millet and sorghum. This was followed by various seed legislations enacted by Government of India. Further, AICRP-NSP (Crops), popularly known as National Seed Project was launched during 1979-80. The NSP-Project came into operation in three major phases and continues to produce breeder seed to cater the needs of the Indian farmers. The project resulted in achieving breeder seed production surpassing the indents in all major crops. The seed programme of the country was further strengthened with NSP II (World Bank) Project starting in 1989-90, which not only supported the ICAR and SAUs, but also Department of Agriculture, Seeds Corporations, Seed Certification Agencies and Private Seed Industries to a great extent in production, processing and in providing quality seeds to the country.

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.

Introduction

In order to implement the sui generis system for plant variety protection for granting PBR to a breeder or farmer or institution, DUS testing is compulsory. A new variety shall be registered, if it conforms to the criteria of novelty, distinctness, uniformity and stability. An extant variety, a variety about which there is a common knowledge shall also be registered within a specified period, if it conform such criteria as distinctness, uniformity and stability.

Once a valid application for PBR is accepted the seed / plant material of the variety will be requested for official DUS tests. These official DUS tests need to be conducted by crop based institutions on behalf of the PPV & FR authority by following universally acceptable test procedures. This necessitated in the development of test guidelines, descriptors and procedures to be followed in each crop. National Test Guidelines have been developed for 96 crops representing harmonized approach for the testing of new varieties which will form the basis for DUS examination. These National Test Guidelines contain details on i) subject of the guidelines, ii) material required, iii) conduct of tests, iv) methods and observations, v) grouping of varieties, vi) characteristics and symbols, vii) table of characteristics, viii) explanations on table of characteristics, ix) literature and x) technical questionnaire. The registration was open for 107 crop species for new variety and for 114 crop species for extant / farmers varieties.

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

Introduction

Seed is a critical and vital input that draws an explicit line between the success and failure of any agricultural production programme. In fact progressive history of agriculture has been a history of seed development and production. The mankind has been attempting to select better seed and employ better seed production techniques volitionally or in-volitionally ever since it divested nomadic life for the settled one. Initial attempts were confined to selection of useful crops followed by selection of better sorts and land races among the available native genetic resources. The introductions, hybridization followed by selection of better types and modern breeding tools inclusive biotechnological interventions have been extensively employed to breed better seed. Considering that research in crop improvement can turn little stone unless the quality seed with desired attributes is made available to the farmers. Government of India set up enforcement of provisions of Seed Act, 1966 for certification of seed as per prescribed minimum standards. Central Seed Certification Board was established in 1972 to exhort the central and state governments for producing genetically and physically pure and physiologically viable seed. The seed production programmes and rules were progressively honed to meet the ground situations. Initially the seed was considered as the exclusive bastion of public sector but the private sector got actively involved in seed production. WTO the seed still became a very open subject and the Seed Act was modified in 1988 and 2001 to permit import and export of quality seed, respectively. Despite of all these positive developments in seed sector, the availability of seed is still far from satisfactory. As on today private sector dabbles in low volume high cost seed due to economics and storage factors but the high volume less cost is still a virgin for private sector and is predominantly done by the public sector. Crop improvement is no more an art and science of improving hereditary of crop plants but has become a starker and competitive business under which the stronger would survive and the weaker get eliminated.

Business was abysmally shattered at the terminal end of the Second World War. This forced some nations to sign some tariff related global

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.

Introduction

Stored-product insects are serious pests of dried, stored, durable agricultural commodities and of many value-added food products and non-food derivatives of agricultural products worldwide. Various estimates on post harvest losses across the country revealed that there is loss of 2–12 per cent during storage exclusively by insects. Almost all the insect species may destroy 10.0 -15.0 per cent of grain and contaminate the rest with undesirable odour. The major loss is done by two internal feeders i.e. rice weevil and grain borer, which are major pests of rice, wheat and millets (Champ and Dyte, 1977). They also help in transportation of fungi (Sinha and Sinha, 1990). The losses during storage are quantity losses and quality losses. Quantity losses occur when insects, rodents, mites, birds and microorganisms, consume the grain. Infestation causes reduction in seed germination, increase in moisture, free fatty acid levels and decrease in pH and protein contents etc. resulting in total quality loss. Quality losses affect the economic value of the food grains fetching low prices to farmers (Das et al., 2013).

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.