Preface Postharvest Technology is a very important branch of agriculture and its importance further increases in the filed of horticulture as the horticultural crops are highly perishable in nature. Although postharvest technology is being practised in all parts of the world since time immemorial, the industry is still in infancy in India. Fruits, vegetables and flowers are produced in many parts of the country but cold chain is missing. Marketing channels are long and delay movement of commodity from producer to consumer. Processing and preservation is also negeigible under organised sector. Therefore, undertaking continuous research, teaching and training becomes imperative in today’s changing era of science. As such, there is no book available which discusses the basics of the subject as instant notes on various topics pertaining to the postharvest management of horticultural crops. The students, teachers and researchers often search for a direct reference which is complete on the subject for teaching the undergraduate students or postgraduate beginners. The author therefore made an attempt to meet out this need. This book on “Postharvest Management and Processing of Fruits and Vegetables” has been divided into 4 parts. Part I deals with Postharvest Physiology, Part II with Processing, III with Novel Technologies and Part IV with Objective questions. Effort has also been made to add few recent topics i.e. pulsed electric fields, magnetic fields, plused light treatment, high pressure technology, functional foods, designer foods, GM foods, HACCP, nutraceuticals under part III alongwith objectives questions that are often asked in various competitive examinations. Contents have been covered considering the syllabus of basic course on postharvest management and processing of fruits and vegetables being taught in most of the agricultural universities in India at undergraduate and postgradute levels.

India, one of the largest food producer countries (I in milk production, II in fruit and vegetable production and III in food grain production at world level), possesses the potential of being the biggest with the food and agricultural sector contributing around 26 percent of the Gross Domestic Product (GDP). It is a paradox that people of the country producing such huge quantities of food including fruits, vegetables, milk, cereals grains etc. are still suffering from many nutritional deficiencies in their diet, and even in some places, the stomachs of people remain unfilled for the want of food. The credit of this would predominantly go to the poor postharvest infrastructure as well as knowhow and accessibility to the facilities. All this makes us one among those countries having largest postharvest losses. The reduction of losses occuring during food handling, processing, storage, distribution and use would be an indirect way of increasing the food production and making the country self-sufficient in nutritional requirements.

Physiological Development Fruits and vegetables can be divided into 3 stages based n their physiological development i.e. growth, maturation and senescence. Growth: This generally refers to cell division, enlargement and differentiation ultimately giving a particular size, weight and volume to the commodity. Maturation: It is initiated before the ceasation of growth and lasts till the onset of senescence. Senescence: The stage when anabolic (synthetic) processes almost terminate and catabolic (degradative) processes are initiated and speeded up causing ageing and finally death of tissues. Ripening: Stage that begins with the last stages of maturation and lasts till the beginning (first stage) of senescence. Ripening is a very important event in the life of a plant as it transforms a physiologically mature but inedible (or not preferred to be eaten) plant part into an edible, visually and olfactorily attractive and tasty commodity. Ripening marks the completion of developmental phase and is an irrevessible event.

Maturity Standards and Harvesting Indices Harvesting : Harvesting is detaching a commodity from the point of its origin. This point of origin may be an above ground plant part i.e. shoot eg. apple, tomato etc. or an underground plant part eg potato, carrot, etc. or in water i.e. harvesting of fish from a pond (not to be covered in this book).

Storage : It can be defined as keeping the commodity fresh or processed in safe condition with minimum of deteriorative changes for later use. Reasons of Deterioration During Storage

Packaging : Packaging of fruits, vegetables, flowers or any other commodity is chiefly done to assemble the produce in convenient units of different sizes, shapes & types for storage, transportation, marketing and distribution. The size of units may vary depending on the requirement e.g for retail marketing smaller units are preferred and for bulk transportation and storage, large units would be more convenient. Why do we Require Packaging? Imagine there is no packaging material and technology available. How we are going to transport apple, mango etc. to distant markets? Definitely as loose. Then how can we weigh or count the fruits being transported or marketed? This would be very difficult. Had there been no packaging the commodity would have suffered great physical, chemical and microbiological losses. It would have been very difficult to handle, manage, transport and market the produce as loose and unpacked. Therefore, the packaging of fresh as well as processed commodities was needed to contain, unitize and protect the produce.

Nature has made such a beautiful system that a fruit does not spoil unless its outer covering is removed and till it is there on the plant. For example banana will not spoil for long time if we do not remove its peel. Similar is the case with apple, guava, mango and many other fruits and vegetables. But as soon as the outer covering is removed the damage begins and the commodity is spoilt very soon. Preservation is extending shelf life of fresh or processed food by using various methods and prevention or reduction of spoilage. Better the preservation, lesser the spoilage, more the spoilage poorer and inefficient is the preservation. Therefore, in order to prevent or reduce the spoilage, we have to first identify and understand the causes of spoilage. There are chiefly 3 agencies that cause spoilage in fruits and vegetables i.e. (i) microorganisms, (ii) enzymes & chemical changes and (iii) man, animals, rodents, insects, etc. For effective preservation we have to check the growth and activity of these spoilage causing agencies. So, in order to prevent spoilage and preserve a perishable commodity for long time the following principles and methods are to be followed.

Essentials for Quality Product Preparation Plant ripened red tomatoes should be selected. Yellow and green fruits on processing yield dull colour and turn brown due to oxidation. Never use iron equipment for processing. Lycopene oxidizes and turns brown when comes in contact with iron. It also forms black compounds with the tannins present in tomatoes or the spices which are used for product preparation. Avoid prolonged heating and cool immediately to avoid over-cooking.

Pickles known to be good appetizers, aid digestion and pallate are edible products preserved and flavoured in a solution of common salt and vinegar. Spices and oil may also be added. There are a number of pickles very popular in India i.e. mango pickle, cauliflower pickle, lime and lemon pickles, ginger chilli pickle etc. But, some pickles like Sauerkraut are not very common in India but are very popular in European countries.

Jam : It is a product prepared by boiling to a suitable consistency, fruit pulp with sufficient quantity of sugar, acid and pectin so as to set and become firm enough to hold the tissues in position. About 45 parts of pulp are used with every 55 parts of sugar. The finished product should not contain less than 68 per cent total soluble solids. Jelly : Jelly is prepared by boiling the fruit pectin extract with sugar in the presence of appropriate amounts of acid so as to set into a clear gel. A perfect jelly is transparent, devoid of haziness or any suspended material well set, but not too stiff and should have original flavour of the fruit. When cut it should retain its shape and show a smooth cut surface. Marmalade : It is a fruit jelly like product in which slices of fruit or peel are suspended in the set gel. Mostly they are prepared from citrus fruits like oranges, lemons etc.

Canning : Process of preservation of various food stuffs including fruits and vegetables whole or in pieces, in sugar syrup or brine by heat processing them in hermetically sealed containers.

Drying/ Dehydration means the process of removal of water. Drying : Removal of water (moisture) by using non conventional energy sources like Sun or wind. Dehydration : Process of removal of moisture by the application of artificial heat under controlled conditions of temperature and / or humidity and air flow.

Freezing : Freezing is a process where temperature of food (fruits, vegetable etc.) is lowered down considerably below freezing point so that the water present inside the food undergoes change in state from liquid to solid (ice) and gets frozen immediately eg Frozen Pea. Water is immobilized and solutes are concentrated to reduce the water activity. Principles of preservation : Combination of low temperature, low water activity, and pre-treatments like blanching, dipping in sugar syrup etc. stop (reduce) the growth and activity of microorganisms. Theory of freezing : Freezing takes place in two main steps

Beverage: It includes all drinks whether they are fermented or unfermented, prepared from fruits or non-fruit, sweetened or unsweetened eg. tea, coffee, coca cola, cider, maaza are all beverages. Fruit Beverages : Beverage which is prepared partly or fully from fruit juice or pulps with or without additives eg. pure fruit juice, squash, cordial, RTS beverage etc. Non-fruit Beverage : Beverage which does not contain any fruit part eg. Coca cola, pepsi, sherbet etc. Unfermented Juice or Pure Fruit Juice: This is the natural juice pressed out of the fruit and practically its composition remains unaltered during preparation and preservation. No additives like sugar, acid, water etc. are added. eg apple juice, orange juice. Fruit Juice Beverage: This is the fruit juice that has been considerably altered in composition by adding water, sugar, acid, flavour, colours, preservatives etc. before consumption. It may or may not be diluted before it is served as a drink eg. squashes, nectars, appetizers etc.

Alcoholic Beverages These are the beverages which are prepared after alcoholic fermentation of sugars by yeast, contain varying amounts of ethyl alcohol (5-42%), and are consumed directly or after dilution in water. Wine : Product made by alcoholic fermentation of grapes or grape juice unless otherwise specified, by yeast (Saccharomyces cerevisiae and a subsequent ageing process. Alcohol content is 11-14 %, but may be as low as 7%.

Enzymes are biocatalysts that change the rate of reaction without being changed themselves. All (Most) enzymes are proteins but all proteins are not enzymes. Ribonuclease is the enzyme which is non- protein in nature. Properties of Enzymes

Spoilage may be defined as the deteriorative process which renders the food inedible or results into reduction of quality. Spoilage is Mainly of Two Types Abiotic Spoilage: Less potential for causing health hazards to consumers. Occurs due to

In a commercial horticultural enterprise, if the product is not marketed properly, safely and beneficially, all the investment, inputs, hard work goes in vain. Basically every commodity that is produced should reach the consumer and marketing is all about how the commodity reaches the consumer. There is no fun of producing any commodity if it does not reach the consumer. The word market has been derived form Latin word “marcatus” meaning merchandise, where people conduct business. Market therefore refers to place where goods/ commodity and services are bought and sold. Marketing is a sum total of business activities through which the goods and services are either bought or sold. Cundiff and Still defined marketing as “the business process by which products are matched with markets and through which transfer of ownership are affected. Why Marketing of Fruits and Vegetables is Complex and Risky as Compared to Other Goods

Before beginning the actual work on the establishment of a Fruit and Vegetable Processing Industry the following points should be considered: Availability and possibilities of obtaining Funds: Investment of own money or obtaining loans from banks etc. The scale of industry (Large, Small, Cottage or Home): Has to be decided based on availability of raw material, funds availability, land, labour and other resources. The location: The processing unit should be located near to the actual production site of raw material so that the transportation costs of high bulk raw materials is reduced. There is no fun or justification of establishing apple processing industry in Lucknow or Bangalore and mango processing industry in Shimla as the related raw materials would have to be transported through long distances. Site: Site selected in the location should be sunny area free from dampness and sufficient space for waste disposal should be ensured.

With the increasing health consciousness of consumers, there has been an increasing concern over the use of thermal processing methods like blanching, pasteurization, sterilization etc. for enhancing the shelf life of foods as these methods fail to preserve the fresh like nutritional, therapeutical and sensory qualities of the food. With the increased consumer demand for fresh and fresh-like foods, interest in minimal processing of foods is increasing. The trend is also shifting from the traditional heat processing to those technologies that employ no or minimum heat application, thereby retaining the quality to a maximum level. One of the ways to accomplish this is via use of non-thermal processes. Over the past few years a number of non-thermal processes or cold preservation methods have been invented and developed. These methods are being evaluated in pasteurization and sterilization of various foods or in the extension of shelf life of various packaged foods. Some of such novel technologies and the products prepared, have been discussed here under. 1. Extrusion Extrusion is a size enlargement process wherein small granular food or powdered particles are re-formed into larger pieces with different shapes, textures, colours and flavours from the basic ingredients. In extrusion food is compressed and forced to pass through a fine opening (die). As soon as it comes out of the opening, the outside pressure is very less as compared to the pressure inside the screw of extruder and the food expands instantaneously. If the food is heated the process is called as extrusion cooking. It is a process which combines several unit operations including cooking, mixing, kneading, shearing, compressing, shaping and forming. Extrusion adds a variety to the products by changing shape, size, texture and even some of the minor ingredients of the food and at a reduced cost than most of the other processing methods. Extrusion cooking (not extrusion) is a high temperature short time (HTST) process that reduces microbial contamination and inactivates enzymes.

1. Multiple Choice Questions

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