When fats and oils in food are oxidized by atmospheric oxygen over time, they develop an unpleasant smell and taste. This process is called Rancidity. Rancid food is not just unpleasant — it can be harmful to health.
Cause: Oxidation of fats by atmospheric oxygen.
Result: Bad smell and taste.
Antioxidants: BHA, BHT, Vitamin E, Vitamin C.
Nitrogen Flushing: Replacing air with inert N₂ in packaging.
Method 1: Using Antioxidants Antioxidants (like BHA, BHT, or Vitamin E) are added to food. They are oxidized preferentially — sacrificing themselves so the fat molecules are not attacked.
Method 2: Nitrogen Flushing (Inert Atmosphere) Food packets are filled with nitrogen gas (N₂) before sealing. Since nitrogen is inert, it does not react with fats, preventing oxidation.
Rancidity is the process by which fats and oils in food undergo oxidation or hydrolysis, producing an unpleasant smell and taste.
1. Adding antioxidants to food. 2. Flushing food packaging with inert nitrogen gas to remove oxygen.
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