A. DEFINITION
Food Science is a study of the physical and chemical constituents of food and the scientific principles underlying their modification, preservation and spoilage.
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B. SCOPE OF FOOD SCIENCE
Food Science is the backbone of several billion dollar food industry. It has helped the food industry to expand and provide products to meet the most difficult requirements and the weirdest imaginations related to foods by the customers. Following are some salient achievements in this context:-
COMBATING UNDERNUTRITION: Low-cost nutritious foods such as chikki and Surichi Meether have been developed to reduce the prevalence of protein energy malnutrition (Kwashiorkar and Marasmus) in the vulnerable populations (children, pregnant women and nursing mothers).
SPACE FOODS: Novel foods have been prepared for Astronauts. Space Foods have a long shelf life, are usually dehydrated, are easy to reconstitute and have a small volume and mass. They are generally packaged in thermostabilized flexible packaging, which should preferably be biodegradable, reusable and edible.
MILITARY FEEDING: Nutrient-dense, lightweight, compact and easily reconstitutable food products with prolonged shelf life at elevated temperatures have been developed for soldiers and military personnel. They are packaged in edible or biodegradable flexible films.
FABRICATED FOODS: Texturized vegetable proteins and texturized soya proteins (soya chunks or granules) are the most commonly available fabricated foods. They have the texture and taste which are similar to meat; therefore, they are often flavoured accordingly. Food analogues for meat, milk and eggs have been developed. Example- natural egg yolk has been replaced with the yolk prepared from vegetable oils, milk solids, emulsifiers, nutrients and additives.
MODIFIED GAS ATMOSPHERE: Modifying the composition of cold storage air, wherein fruits and vegetables are stored, helps to enhance the shelf life and regulate the ripening process. Quick freezing of fruit and vegetable pulps has improved markedly their non-seasonal availability; for example, the use of mango pulp in mango-based drinks.
NUTRACEUTICALS: Most Nutraceutical products have been developed with the help of Food Science. Example- the n-3 fatty acids such as eicosapentaenoic acid and docosahexaenoic acid have been extracted from liver of large fish such as whale and are being used for the prevention treatment and management of several degenerative diseases such as elevated cholesterol, heart diseases, certain cancers and arthritis. Dietary fibre has been isolated from several foods such as, guar-gum from broad beans and pectin from fruits and are being used for the treatment of constipation, obesity, etc.
BIOFORTIFICATION: Biofortification of crops has also witnessed success with the help of food science. Example- rice with high iron content has been developed by International Rice Research Institute, Philippines and Manila.
PREBIOTICS: The advent of prebiotics has created a stir in the food and health industries. These modulate the activity of colonic microflora and also influence the health positively. Example- lassi, curd and yoghurt etc.
FOOD AIDS OR SPECIAL INGREDIENTS: Specific components from natural foods are being extracted or isolated and used in various recipes. Whey protein concentrates and whey protein isolates have been extracted from whey water and are being used in the preparation of breads, cakes, muffins and health drinks. Lactose extracted from milk is used as a sweetness moderator along with sucrose and is used to improve the texture/bulk of biscuits.
FAT AND SUGAR SUBSTITUTES: Several carbohydrate and protein based fat substitutes and fat replacers have been developed, such as sorbestrin. They have been used successfully in the development of several bread spreads, table spreads, salad dressings and bakery products. Polydextrose have been used to develop sugar substitutes.
RECENT TRENDS IN PACKAGING: Advancements in packaging include controlled atmosphere packaging (CAP), modified atmosphere packaging (MAP), intelligent and active packaging and radiofrequency identification (RFID) technology. CAP & MAP prevent microbial growth. Intelligent and active packaging informs customer about storage conditions of food prior to purchase. RFID technology helps in tracking the movement of food once it leaves the manufacturing unit for distribution and sale. Thus, if a food expires on retail shelf, it can be brought back by the manufacturer and discarded. This ensures safe consumption of food. Edible packaging films are being prepared from various proteins and carbohydrates.
NANOTECHNOLOGY: It is being used for isolating, modulating or manufacturing flavours, antioxidants and nutraceuticals. Such products are called nanostructures. This technology has been employed for designing membrane-based separation systems such as those required during freeze dehydration.
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C. INTER-RELATIONSHIP OF FOOD SCIENCE WITH FOOD CHEMISTRY, FOOD MICROBIOLOGY AND FOOD PROCESSING
Food Chemistry is the science that deals with the composition, structure and properties of food and with chemical changes that take place in food.
The chemical composition of food dictates which microorganisms can grow on it and the changes which take place in the food because of their growth. The changes may be planned and desirable or may result because of contamination, causing disease or just spoiling the food rendering it unfit for consumption.
Microorganisms have basic growth requirements, namely food, moisture, temperature, time, etc.
This is where Food Chemistry and Food Microbiology gets related to Food Processing. The processes to which food needs to be subjected to improve its taste, texture, flavour, etc., depend on its composition and ingredients. The time and temperature for food processing depend not only on the chemical composition of food but on its microbial load and the type of packaging to be used.
Example:-
Production of curd from milk: Milk has sugar lactose, on which the bacteria Lactobacillus feed. As they grow and divide they turn the milk sugar into lactic acid. This acid denatures the milk protein casein from a globular protein to a fibrous protein. This gives milk a thick texture and it gets converted into curd. Optimum temperature (mild hot- 35 degree to 40 degree C) is to be provided to the bacteria to grow properly in the milk.
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Compiled & Created by: Rukmini Ganguly
Source: ** FOOD SCIENCE & NUTRITION by SUNETRA RODAY (OXFORD UNIVERSITY PRESS)
** FOOD SCIENCE NUTRITION AND SAFETY BY SUKHNEET SURI & ANITA MALHOTRA (PEARSON)
Assistant Lecturer- IHM Gurdaspur
