What is rancidity ?
The spoilage of food or oxidation of food in such a way that it becomes unpleasant smell , undesirable for consumption. Food turns rancid when the fats and oils within them get oxidized and the taste and smell of the food change due to this reason.
e.g.: Oil becomes rancid due to the decomposition of fats it contains or sometimes milk becomes rancid due to not heating it in a humid atmosphere, etc. How to control rancidity
Rancidity can be controlled by Adding antioxidants (BHT ,BHA) to foods. Keeping food items in a closed container. Refrigerating food can also help in reducing rancidity. Replacing oxygen in the containers with another gas.
When fats and oils are oxidised, they become rancid and their smell and taste change. Usually substances which prevent oxidation (antioxidants) are added to foods containing fats and oil. Keeping food in air tight containers helps to slow down oxidation. Do you know that chips manufacturers usually flush bags of chips with gas such as nitrogen to prevent the chips from getting oxidised .