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Fat Modifications |
To improve application of vegetable oils in food products they may often be chemically or physically modified to change their properties.The main processes are fractionation, hydrogenation and inter_esterification. |
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Fractionation |
Many Oils especially Palm Oil is present in the form of a mixture of high melting point fraction and of a liquid low melting point fraction. The purpose of fractionation process is to separate the liquid fraction called “olein” from the crystallised fraction called “stearin”. |
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The process comprises three steps: |
1. |
Melting of the oil. |
2. |
Selective crystallization in several cooling steps. |
3. |
Separation of the olein from the stearin by filtration. |
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Hydrogenation |
Hydrogenation is a fat modification process mainly used on liquid oils like soya, rape, cotton or sunflower to increase their melting properties by reducing their degree of unsaturation.
Hydrogenation is a reaction involving the use of a catalyst, most generally nickel, temperature and the quantity and flow of hydrogen injected, all of which are essential to guarantee
selective hydrogenation. |
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Interesterification |
Inter esterification consists in modifying the physical properties of the oil by an interchange of fatty acids between different triglycerides. This is done by use of a catalyst operating at about 100°C and under vacuum. |
The objective is to |
1. |
Change the overall melting profile. |
2. |
improve the compatibility. |
3. |
Improve the plasticity. |
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