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You are currently using guest access (Log in), , Crop Process Engineering 3(2+1), , Home P Courses > Existing Courses ® UG Courses - Agricultural Engineering Agricultural Engineering B CPE ® Module- 1 Scope and, importance of food processing... P Lesson 2. Methods and Principles of Food Processin..., , Navigation i Lesson 2. Methods and Principles of Food Processing (Part I), Home, Site pages + . ., The Green Revolution, better management practices and subsequent efforts through, Current course nh Bcoct i % : o, ee the application of science and technology for increasing food production in India, i have brought self reliance in food. The nation become self reliance but available, ® Participants ‘ *, é i produce could not reach to the consumer so we are, still facing the problem of use of, eneral, , under nutrition and malnutrition. Properly planned agri-produce if process, it can, Module- 1 Scope oS : :, and importance of reduce the waste, enhances employability and can contribute to the economic, food processing... development of rural population at large., , | Lesson 1. Scope, and importance, , of food, processing The fruits and vegetables are comparative higher value than cereals and more perishables., Vv Lesson-1 Quiz Losses in the fruits and vegetables are high and chances to reduce the waste and enhancing, Lesson 2, the employability through post harvest processing are more. The processing includes prepetlelelte processing of fruits and vegetables before these are fit to final conversation into processed, Food foods. The food preservation and processing industry has now become of a necessity than, Processin... being a luxury. It has an important role in conservation and better utilization of fruits and, @ Lesson 2 Quiz vegetables. In order to avoid the glut and utilize the surplus during the season, it is, | Lesson 3. necessary to employ modern methods to extend storage life for better distribution and also, aaa’ rocessing techniques to preserve them for utilization in the off season on both large scale, Principles of P ig iq’ Pp Z 2, Food and small scale., Processin..., Y Lesson- 3 Quiz Food processing therefore refers to the application of techniques to foods in a systematic, Module- 2 manner for preventing losses through preservation, processing, packaging, storage and, Processing of farm distribution, ultimately to ensure greater availability of a wide variety of foods which, we would help to improve the food intake and nutritional standards during the periods of low, Module- 3 availability. The main objective of fruits and vegetables processing is to supply wholesome, Processing of safe, nutritious and acceptable food to consumers throughout the year., animal products, Module- 4 Principal Prerequisites of preservation are cleaning, grading and sorting as per maturity., of size reduction, . . oo, . . ., grain shape... 1. Cleaning: It is a unit operation in which contaminating materials are removed from, Module- 5 Theory of the food material and separated to leave the surface of the food in a suitable condition, ities pee of for further processing. In vegetable processing, blanching also helps to clean the, mixtures for..., , product. In addition, the early removal of small quantities of food contaminated by, , Module- 6 Theory of : : ca fen., 2 micro-organisms prevents the subsequent loss of the remaining bulk by microbial, , separation, size and, , un sized ... growth during storage or delays before processing., , Module- 7 Theory of, , filtration, study of Wet cleaning: Wet cleaning is more effective than dry methods for removing soil, different. from root crops or dust and pesticide residues from soft fruits or vegetables. It is also, Module- 8 Scope & dustless and causes less damage to foods than dry methods., , importance of, , Mralonal hanes Dry cleaning: Dry cleaning procedures are used for products that are smaller, have, greater mechanical strength and possess lower moisture content (for example grains, and nuts). After cleaning, the surfaces are dry, to aid preservation or further drying., , The main groups of equipment used for dry cleaning are;, , Courses, , - air classifiers, - magnetic separators, , - separators based on screening of foods

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Removing contaminants and foreign bodies: Physical separation of contaminants, from food is possible when the food has regular well defined shape. e.g. round foods, are separated from contaminants by exploiting their ability to roll down in inclined,, upward moving conveyor belt., , 2. Sorting: Sorting is the separation of foods into categories on the basis of a, measurable physical property. Like cleaning, sorting should be employed as early as, possible to ensure a uniform product for subsequent processing. The four main, physical properties used to sort foods are size, shape, weight and color., , Shape and size sorting: The particle size distribution of a material is expressed as, either the mass fraction of material that is retained on each sieve or cumulative, percentage of material retained. Size sorting is the separation of solids into two or, more fractions on the basis of differences in size., , Color sorting: Small particulate foods may be automatically sorted at high rates, using microprocessor controlled color sorting equipment. Particles are fed into chute, one at a time. The angle, shape and lining material of chute are altered to control the, velocity of pieces as the pass a photo detector. Photo detectors measure the reflected, color of each piece and compare it with preset standards, and defective foods are, separated by a short blast of compressed air., , Weight sorting: Weight sorting is more accurate than other methods and is therefore, used for more valuable foods. Aspiration and flotation sorting use differences in, density to sort food and are similar in principle and operation to aspiration and, flotation cleaning., , 3. Grading: This term is often used interchangeably with sorting but strictly means, ‘the assessment of overall quality of a food using a number of attributes’. Grading is, carried out by machines or operators who are trained to simultaneously assess a, number of variables., , The basic principles of preserving bio materials and their respective methods are, given in the following table., , , , Sr., , , , , , , , , , , , , , No. Principle Method, , Reduc ing temperature so that wage Evaporating Coo] ChamberRefrigerated, 1 deteriorating reactions occurring within StoraeeCold storaeeFreezin, , the bio materials are minimized 8 storag e, , Creation of ano nyaronment of gases such Hermetic StorageControlled Storage, 2 | deteriorating bio chemicals reduce their ae :, , pare and Modified Packaging, , activities., , Reduce chemical potential of water, , (water activity reduction) . . ., , Drying and Dehydration, Convective, 3 1. Application of heat microwave drying, pasteurization and, 2. Addition of solute so that water is sterilizationOsmo-dehydration, strongly bound, , Production of chemicals through PicklingControlled, , 4 | fermentation which will be detrimental ~ : : :, i : : fermentationAerobic, Anaerobic, to the microbes causing food spoilage, 5 Irradiations, Dielectric, infrared and, , 5 Innovative methods, , Ohmic heating