The Preservation Of Foods Essay Research Paper

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The Preservation Of Foods Essay, Research Paper The preservation of food. Different government organisation, such as the world Health (WHO) and the United Nations Foods and Agriculture Organisation (FAO) have different definitions of food additives. In laymen terms, a food additive is any substance added to food. Definition: ” Any substance the intended use of which or may reasonably be expected to result directly or indirectly in its becoming a component to otherwise affect the characteristics of any food ” Mechanisms of action of food Preservation procedures, G.W.Gould. page 2 The food Protection committee of the institute of medicine’s Food and Nutrition Board Defines and additive as a ” substance or mixture of substance, other than a basic foodstuff, which is

present in a food as a result of any aspect of production, processing storage, or packaging “. Types or different form of food preservatives Food preservatives are classified into two main groups: antioxidants and antimicrobials, + Antioxidants are compounds that delay or prevent the deterioration of foods by oxidative mechanisms. For example, enzymes called phenolases catalyse the oxidation of certain molecules (e.g., the amino acid tyrosine) when fruits and vegetables, such as apples, bananas, and potatoes, are cut or bruised. The product of these oxidation reactions, collectively known as enzymatic browning, is a dark pigment called melanin. Antioxidants that inhibit enzyme-catalysed oxidation include agents that bind free oxygen (i.e., reducing agents), such as ascorbic

acid (vitamin C), and agents that inactivate the enzymes, such as citric acid and sulphites. + Antimicrobial agents inhibit the growth of spoilage and pathogenic micro-organisms in food. Antimicrobials are most often used with other preservation techniques, such as refrigeration, in order to inhibit the growth of spoilage and pathogenic microorganisms. Sodium chloride (NaCl), or common salt, is probably the oldest known antimicrobial agent. Organic acids, including acetic, benzoic, propionic, and sorbic acids, are used against micro-organisms in products with a low pH. Refer to the fig 1 in appendix to see a list of common preservatives used in the food industry. What are the main reasons for food preservatives? Food Preservatives are used in food for four main reasons. 1. To

maintain Product consistency. Emulsifiers give a product a consistent texture and prevent them from separating. Stabilisers and thickeners give smooth uniform texture. Anti-caking agents help substance such as salt to flow freely. 2. To maintain palatability and wholesomeness. Preservatives retard product spoilage caused by mould, fungi or yeast. Bacterial contamination can cause foodborne illness, including life-treating botulism. Antioxidants are preservatives that prevent fats and oil in baked and other good from becoming rancid or development an off flavour. They also prevent cut fresh fruits such as apples from turning brown when exposed to air. 3. To provide controlled acidity. Some food preservatives like sorbic acid help modify the acidity and alkalinity of foods for

proper flavour, taste and colour. 4. To enhance flavour or impact desired colours. Many spices and natural and synthetic flavour enhance the taste of foods. Colours like wise enhance the appearance of certain foods to meet customer expectations. In addition, many substances added to foods may seem unheard of when listed on the ingredient label, but are actually quite familiar. For example, ascorbic acid is another name for vitamin C, alpha is another name for vitamin E and beta-carotene is another source of vitamin A Types of food Preservation techniques Low-temperature preservation Storage at low temperatures prolongs the shelf life of many foods. In general, low temperatures reduce the growth rates of microorganisms and slow many of the physical and chemical reactions that