Читать книгу Food Chemistry. The Role of Additives, Preservatives and Adulteration онлайн

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Unsaturated fats are the most widely recognized atoms attacked by the process “oxidation” that makes them rancid. Oxidized lipids are regularly stained and result in displeasing tastes, for example, metallic or sulfurous flavors. It is essential to keep away the food from oxidation. These kinds of food are hardly preserved with the help of drying, and they are usually preserved with the help of salting/pickling, smoking, and fermenting. Before air drying the fruits which are less fatty foods are sprayed with antioxidants (sulfurous). Metals act as a catalysis in the process of oxidation, so it is better if fat oils like butter should not be kept in the Al foil or in any other metal container. Olive oil are halfway shielded from oxidation by their inherent antioxidant property but rest is sensitive toward photooxidation. Antioxidant additives are additionally added to fat based beautifying agents, for example, lipstick and lotions to forestall rancidity.

These are used as preservatives in pickles. Oil makes a protective covering and prevents contact of microorganisms and air with the food. Spices do not have bactericidal effect in concentrations usually used. Cinnamon and cloves containing cinnamic anhydride and eugenol, respectively, are more bacteriostatic than other spices. Extracts of garlic onion cabbage are inhibitory to Bacillus subtilis and E. coli [92].