Animal fats

FOOD SCIENCE AND PROCESSING 3 (2+1)
Lesson 12 : Composition, Nutritive Value and Processing of Nuts and Oil Seeds

Animal fats

  • Butter: Cream pasteurized to inactivate lipase and destroy microorganisms. Starter added to produce lactic acid which alters flavor. Cream churned by agitation by adding H2O forms batter by the coalesee of fat globules by rupturing the protein – surrounded by each globule. Salt can be added to butter.

    Ex. Oil in water emulsion

  • Lard:
    • Lard is an animal fat of pigs
    • Prepared by heat rendering of fatty tissues.
    • The quantity of lard depends on the location of fatty tissues in the animal and the method of heating.
    • Methods to delay the rancidity
      • Autoxidation
      • Bleaching
      • Homogenisation
      • Deodorisation
      • Adding emulsifiers

  • Margarine
    • Margarine is used as a substitute for butter made from vegetable oils like soya bean, cotton seed etc., mixture of vegetable and animal fat by hydrogenation.
    • Made from one or more optional fat ingredients churned with cultured pasteurised skimmed milk (SM) or whey.
    • vitamin A & D can also be added to enhance nutritive value
    • Other ingredients that can be added are
      • Lactin monoglycerdes and/or
      • Fat forming fatty acids
      • Emulsifying agents
      • Artificial colors
      • Salt
      • Citric acid /certain citrates / sodium benzoate – as preservative to the extent of 0.1%.

  • Emulsions
  • Emulsions are dispersion of one liquid in another liquid with which it is immiscible.

    • Temporary emulsion: Oil + water shaken together – but on standing oil particles separate from water.
    • Ex. French dressing rasam seasoned with oil.

    • Permanent emulsions: Apart from water and oil a 3rd substance called emulsifying agent or emulsifier is necessary to stabilize the emulsion.
    • Stabilizer/ emulsifiers used

      • Egg yolk
      • Whole egg
      • Gelatine
      • Pectin
      • Starch paste
      • Casein
      • Albumin and
      • Fine powders such as
        1. Parika
        2. Mustard

      Ex.

      • Cake batter – egg, casein, gelatin, starch flour
      • Sambar, kitchedi, payasam – proteins starch and oil
      • Mayonnaise oil (liquid + lemon juice/vinegar (liquid + Egg yolk (lipo protein) emulsifying agent
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Last modified: Friday, 9 December 2011, 10:38 AM