03 September 2012


Rancidity: a specific limit to decompose odor and flavor of a fatty substance that is not preferred.
Damage fats / oils there are 2 types:
1. hydrolytic rancidity
· A hydrolysis triglicerida à glicerol + free fatty acids to produce odor and flavor unwanted
· Enzyme lipase is an enzyme that can hydrolyze triglicerida
    triglicerida + H2O + lipase glicerol free fatty acids
     enzyme is easily destroyed by heat.
· Odor and flavor produced varies, depending on the type of free fatty acids are released.
Eg short chain fatty acids. : As. butyric, caproic, capric, produce undesirable odor because it is volatile at room temperature. Komponen2 fatty acids are found in butterfat triglicerida.
Long-chain fatty acids (which are components of the fatty acids found in many vegetable oils and meat fat): à non-volatile at room temperature and does not cause off flavor as long as it is not oxidized.
2. oxidative rancidity

     is the result of a process autooxidasi fats / oils which komponen2 unsaturated fatty acids spontaneously bind oxygen.
     Komponen2 unsaturated fatty acids on triglicerida greatly responsible for the oxidative rancidity
     Reaction occurs:

- CH2 - CH = CH - H - CH - CH = CH -
component fatty acid radicals

- * CH - CH = CH - O2 - CH (OO *) - CH = CH -
free radicals

- CH (OO *) - CH = CH - + - CH2 - CH = CH -
                                                 component fatty acids to 2

     - CH (OOH) - CH = CH - + - * CH - CH = CH -
        Hidroperoxide 2nd free radical


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