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The scope of the Skill Enhancement Course would include hands on training in pre-selected vocations. It would involve creation of facilities in the form of instructional farms, model plants or engineering workshops. The training programme would lean heavily on practice in technologically advanced methodologies for production of agricultural crops, fruits, vegetables, ornamental, medicinal, aromatic, forest plants including fiber and fuel crops etc. It would also engage students in integrated farming systems consisting of production of fish, poultry, livestock for milk, eggs, meat and wool, and processing for value added products etc. The other avenues of practical training would include internships in private industrial houses, technology transfer and rural development programmes. The practical exposure would also involve students in preparation of project feasibility and implementation reports, proper methods and procedures for maintenance of records including inventory of materials, maintenance of accounts, and management of the enterprise. The Post Harvest Processing Technology in the area of fruits and vegetables has to match with the production of these perishable commodities to reach the consumers. For a successful food-processing sector, various aspects such as quality control, quality system and quality assurance, and the constituents of the total quality management should function in a horizontal fashion. Processed Foods have to be safe and nutritious to sustain the dayto- day lives of millions of people and hence needs eternal vigilance to avoid related health hazards. The students are expected that to read the laboratory procedures before class so that he or she may perform experiments more efficient and understand the reason for the results obtained. A unique aspect of this manual is inclusion of considerable background information on the relevant of Post Harvest Processing Technology with lab exercise to demonstrate these principles. Thus, students have all the relevant background information at hand to understand a lab exercise. In last we sincerely invite the readers to feel free and write to us expressing their appropriate opinions, critical comments and constructive suggestions.

Principles The quality of foods can be defined as the ‘composite’ of those ‘characteristics’ that differentiate individual unit of a product and have significance in determining the degree of acceptability of that unit by the consumer. The overall quality refers to technological, physiological, chemical, microbiological, nutritional; and sensory parameters to achieve the wholesome food. Sensory quality attributes such as taste, colour, texture, flavour and overall quality of any food products were evaluated by 9- point Hedonic rating test is used for the purpose of evaluation. This test measures the consumer’s acceptability.

Principle Jam: Jam is a product made by boiling the fruit pulp with a sufficient quantity of sugar to reasonable consistency, firm enough to hold fruit tissues in position. Apple, pear, sapota, apricot, carrot etc. are used for preparation of fruit jam. Jam contains 0.5-0.6 % acid and invert sugar should not be more than 40 %. Total soluble solids (TSS) The TSS value is defined as the amount of sugar and soluble minerals present in fruits and vegetables. A refractometer is based on the principle of total refraction. This is done by placing a few drops of distilled water on the prism in the specimen chamber of the back the cover. The distilled water reading should be zero. If it is not so, it should be set to zero with the scale correction knob. The specimen chamber is now cleaned with muslin cloth or tissue paper. For determining the TSS, a drop of sample (jam, juice and syrup, etc.) is placed on the prism and the percentage of dry substance in it read directly on scale in refractometer.

Principle Jelly: Jelly is a semi-solid product prepared by boiling a clear, strained solution of pectin containing fruit extract, free from pulp, after the addition of sugar and acid. A perfect jelly should be transparent, well set, but not too stiff, and should have the original flavour of the fruit. It should be of attractive colour and keep its shape when removed from the mould. Pectin (0.5-1.0%), acid (0.5-0.75%), sugar (65%), and water are the four essential ingredients. Pectin test and determination of end-point of jelly formation are very important for the quality of the jelly. Some recipes for jelly making are given below:

Objective: Development of RTS beverage from seasonal fruits. Material required Fruit, juicer-mixer-grinder, preservatives, sugar, refractometer, pan and knife etc. Principle Ready To Serve(RTS): This a type of fruit beverage which contain at least 10% fruit juice and 10% total soluble solid besides about 0.3% acid. This is not diluted before serving. Before undertaking the preparation of beverage, it is necessary to know techniques of extraction of pulp/juice from various fruits used for RTS.

Principle Squash: A fruit juice squash essentially consists of juice containing moderate quantity of fruit pulp to which cane sugar is added for sweetening e.g. orange squash, plum squash. This is a type of fruit beverage containing at least 25 percent fruit juice/pulp and 40-50 percent total soluble solids, commercially. It also contains about 1.0 percent acid and 350 ppm SO2 or 600 ppm sodium benzoate. It is diluted before serving. Mango, orange and pineapple are used for making squash commercially. It can also be prepared from lemon, lime, guava, pear, apricot, muskmelon, papaya etc., using potassium metabisulphate (KMS) as preservative, or from jamun, passion fruit, peach, phalsa, mulberry, raspberry, straw berry, grapefruit etc., with sodium benzoate as preservative.

Principle Nectar: The term ‘fruit nectar’ is used to designate pulpy fruit juice blended with sugar syrup and citric acid to produce a ready-to-drink beverage. In this fruit beverage contains at least 20% juice/pulp and 15% total soluble solid and also 0.3% acid. It is not diluted before serving. Many fruit juices are either too acidic or strongly flavoured; these cannot be pleasant without dilution of blending or both. These strong, tart juices are delicious after dilution with thin syrup or blend juice e.g. apricot, guava and plum juice. Out of the tropical fruits, nectars made from banana, guava, mango and papaya are quite popular. The product is sealed in container or glass bottles and processed by heat to prevent spoilage. The fruit ingredients may be puree, pulp, juice or concentrated equivalent to 40 percent of the finished products. Apples, cherries and pineapples are used in combination with others fruits. The sweeteners are sugar, invert sugar syrup, dried corn syrup, glucose syrup and the optional ingredients are lemon juice, citric, malic and fumaric acids as acidifier and ascorbic acid as antioxidants (150 ppm) can be used.

Principle Chutney and sauces are important food products prepared both in homes as well as commercially in India. They improve the digestion and are good appetizers. Tomatoes are a good source of vitamin C. Fresh tomatoes are very refreshing and appetizing but can not be stored for a long period. Often they are sold at distress prices during the peak harvest season and nearly 25% of the produce is spoiled due to mishandling and improper processing facilities. Such losses can be reduced by converting fresh tomatoes in to delicious product like paste, puree, juice, ketchup/sauce and powder. Generally, the sugar content in ketchup/sauce varies from 10-26%. The salt content of the product should be 1.3 to 3.4%. Good quality vinegar is essential for the preparation of high quality sauce/ketch up. It should contain 5.0-5.5% acetic acid or glacial acetic acid (100% acetic acid) and should be added when the product has thickened sufficiently. Tomato sauce/ketchup generally contains 1.25-1.50% acetic acid. In order to increase the viscosity and prevent the separation of pulp from clear juice, pectin can be added to extent of 0.1-0.2% pectin by weight of the finished product. Add 0.025% sodium benzoate as preservative to the product before bottling and then pasteurize.

Principle Pickle is an edible product preserved and flavoured in a solution of common salt and vinegar. Spices and oil are also added. They add to palatability of a meal, aid in digestion and are good appetizers too. Pickles are prepared from fruit and vegetables like cauliflower, reddish, carrot, green chili, turnip, cabbage, onion, mango, jackfruit, aonla and lemon etc. Commercial preservation of many pickle relied upon conversion of fermentable carbohydrates by lactic acid bacteria to organic acids during bulk storage and/or the addition of sufficient amount of sugar, vinegar and other ingredients to the fully cured and packed products to preclude any microbial growth. Organic acids, oil, salt and spices all have antimicrobial properties at suitable concentration especially in combination which preserves the pickles. Pickles in brine such as or after fermentation however, need some amount of preservative or pasteurization to prevent the spoilage.

Materials required Material : Wheat Flour (1000g), Shortening (350 g), Fine Sugar (400 g), Sodium bicarbonate (10 g), Dextrose solution (100 ml) i.e 25 g Dextrose hydrate in 500 ml water, Distilled water (50 ml), salt (8 g). Equipments: Mixer, rolling pin, Tray, cookies cutter, baking oven etc. Principle: Cookies are made from soft wheat are having high sugar and fat content. They contain relatively low moisture content and have fairy high shelf life. Biscuits are similar name used in Europe and UK. Cookies are chemically leavened. Sugar and shortening are creamed to form dough with flour and leavening agents. When cookies dough enters the oven, the fat starts melting and sugar is dissolved which allow the cookies to spread as a function of gravity. The leavening agents expand it in all direction and structure is stabilized with high temperature prevailing in the oven.

Materials required Material : Wheat Flour (550 g), Pearl millet Flour (50 g), Ragi Flour (50 g), Finger millet Flour (50 g), Barley Flour (50 g), Sorghum Flour (50 g), Foxtel Millet Flour (50 g), Maize Flour (50 g), Oat Flour (50 g), Besan (50 g) Shortening (350 g), Fine Sugar (400 g), Sodium bicarbonate (10 g), Distilled water (50 ml), salt (8 g). Equipments: Mixer, rolling pin, Tray, cookies cutter, baking oven etc. Principle: Cookies are made from soft wheat are having high sugar and fat content. They contain relatively low moisture content and have fairy high shelf life. Biscuits are similar name used in Europe and UK. Cookies are chemically leavened. Sugar and shortening are creamed to form dough with flour and leavening agents. When cookies dough enters the oven, the fat starts melting and sugar is dissolved which allow the cookies to spread as a function of gravity. The leavening agents expand it in all direction and structure is stabilized with high temperature prevailing in the oven.

Procedure 1. Mix the dough with ingredients I. Keep it for fermentation till breaks easily without stretching. 2. Put the sponge to mixer. Add salt, sugar, flour and optional ingredients and mix. In last, add shortening. The dough should be soft and very smooth. 3. Let the dough relax for about 30 min. cut pieces of dough weighing 100 g/450g. 4. Mould in along oblong shape and place in baking pans. 5. Proof the moulded dough to a desired height. 6. Bake at 210oC to a golden colour. 7. Cool the loaves overnight. 8. Cut the rusk of desired thickness. Arrange on baking sheets and toast at 190oC till these are crisp and golden brown in colour. 9. Cool and packaged.

Objective: Development of Sugarcane Vinegar. Principle: Sugarcane is one of the main crops worldwide, and it has an important impact on environmental issues. Sugarcane is used in daily routine life in many ways like as vinegar, jiggery, juices etc. In India sugarcane crop is best cultivated in the west U.P. Sugarcane original vinegar drink with high nutritional quality was produced from fresh sugarcane juice using the yeast culture and acetic acid bacteria by fermentation techniques such as submerged alcoholic fermentation followed by acetic fermentation at room temperature. Refined sugarcane is the primary product of sugarcane juice, during its processing; various other valuable products are also obtained in an unrefined form such as brown sugar, molasses, jaggery and vinegar. Sugarcane juice is widely used in the treatment of jaundice, hemorrhage, dysuria, and other urinary disease. Nowadays sugarcane vinegar is also used in Indian kitchens commonly in pickles, salads, etc. Vinegar is extremely useful for human health including antimicrobial activity, blood pressure reduction, antioxidant activity, reduction in the effects of diabetes, and prevention of cardiovascular disease. Vinegar can be made from any carbohydrate source, amylaceous, or sugary substrate through two successive fermentations: alcoholic fermentation, which is carried out by means of yeasts, and acetic fermentation, with acetic bacteria as the protagonist.

Objective: Preparation of Turmeric powder Turmeric (Curcuma longa L), the ancient and sacred spice of India known as ‘Indian saffron’ is an important commercial spice crop grown in India. It is used in diversified forms as a condiment, flavouring and colouring agent and as a principal ingredient in Indian culinary as curry powder. It has anti-cancer and anti-viral activities and hence finds use in the drug industry and cosmetic industry. 'Kum-kum', popular with every house wife, is also a by-product of turmeric. It finds a place in offerings on religious and ceremonial occasions. A type of starch is also being extracted from a particular type of turmeric. The increasing demand for natural products as food additives makes turmeric as ideal produce as a food colourant. India is the largest producer, consumer and exporter of turmeric in the world.

Objective: Development of Potato chips Potato is a perishable commodity and cannot be preserved longer in fresh form. Although for some time potatoes can be preserved by low temperature storage but this low temperature storage results in many undesirable biochemical changes in the quality of the potatoes. Another alternative for the preservation of potatoes is to conversion in the shelf stable value-added processed products. Further, value-addition and processing of potato will also ensure the availability of wholesome, safe, nutritious, and acceptable food to consumers throughout the year along with simultaneous reduction in post-harvest losses and profit to the farmers for their produce. Potatoes are processed into a great variety of products, including cooked potatoes, par-fried potato strips, French fries, potato chips, potato starch, potato granules, potato flakes and dehydrated diced potatoes and others. Globally, only two potato-based snack foods i.e., chips/ wafers and French-fried potato are the main value-added products of potato, accounting for more than 42% of the potato based processed products. Such type of fried products is loved for convenience and their premium taste, flavour, and texture. With the technological advancements, now potato processing is highly industrialized and market driven. Like other processed products, the finished product quality of potato based value-added products severely depends upon the quality of raw potatoes used. Therefore, the major challenge in potato processing is to fulfil the tuber quality requirements specifically, tuber morphology, reducing sugar (=0.1%) and dry matter content (=20%). Alternatively, we can infer that all type of potato is not suitable for processing. The crispy texture of potato chips is one of the most important quality indicators of the finished product, apart from colour, odour and flavour. Potato chips texture is often described in terms of crispness, hardness and crunchiness. This crispy/crunchy character is an important sensory characteristic on which consumers base their appreciation.

Objective: Development of Salted Banana chips. Banana is the second most significant natural product harvest of India close to mango. It is accessible round the year and due as it would prefer, nutritive and the rape tic worth. It is most loved product of all classes of individuals. It is a rich wellspring of sugar and nutrients especially nutrient B. Banana assists with diminishing the danger of heart illnesses. Banana is a famous organic product because of its low cost and high nutritive worth. Banana contains about 20% sugar and sensible measure of Vitamins A, B and C. This is considered to be a rich source producing food. It is consumed in several forms and among many worth added arrangements, Banana Chips is viewed as the main thing. Seared banana chips are typically delivered from under-ready banana cuts southern style in sunflower oil or coconut oil. These chips are dry (like potato chips), contain about 4% water (table), and can be salted, spiced, glossed over or jaggery covered. Some of the time banana enhancing is added.

Objective: Production of Chocolate. The major ingredient of chocolate is cocoa mass, which is mixed with sugar, and in case of milk chocolate, also with milk powder. The conching process then follows, which is important for the development of full chocolate flavour. Melted cocoa butter is added, the chocolate mass becomes liquid and is cooled, tempered and poured into moulds to form chocolate products. Mixing of ingredients Sugar, cocoa mass and milk powder are intensively mixed forming a dry powder. This powder is pre-ground in various types of mills and then finely ground in a 5-roll refiner. The size of particles in chocolate is between 15- 70 mm (average 25 mm). Small operators use vertical ball mills. Optimum flow properties are required for further processing. The yield value required differs according to the potential use (e.g. hollow moulding or enrobing). The particle size affects both the yield value and the plastic viscosity. In order to reduce recipe costs, the most expensive major constituent (i.e. fat) should be used in the smallest possible proportion which will give correct flow characteristics.