Q3 of 20 Page 143

Answer the following:

Suggest some measures to avoid rancidity of oils.

When we use old, left over cooking oil for making food stuff, it is found to have foul odour called rancidity.


i) Rancidity is an oxidation reaction.


ii) When oils or fats are left aside for a long time, they undergo air oxidation and become rancid.


iii) By keeping food in air tight container helps to slow down oxidation.


iv) Rancidity in the food stuff cooked in oil or ghee is also prevented by using antioxidants.


v) Usually antioxidants such as nitrogen gas flushed into bags containing food.


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