Define Rancidity. Give two measures to prevent it.

Answer

**Step-by-Step Solution:**

1. **Definition of Rancidity:**
Rancidity refers to the process of oxidation of oils and fats present in food materials, which leads to the formation of undesirable and often foul-smelling compounds. This process can negatively affect the taste, smell, and safety of the food.

2. **Measure 1: Use Airtight Containers**
One effective way to prevent rancidity is to store food in airtight containers. By doing this, you limit the exposure of the food to oxygen, which is a key factor in the oxidation process that leads to rancidity. Airtight containers help to keep the food fresh for a longer period.

3. **Measure 2: Refrigeration or Inert Gas Packaging**
Another measure to prevent rancidity is to keep the food in a refrigerator. Lower temperatures slow down the oxidation process. Alternatively, food can be packaged with inert gases, such as nitrogen. This method displaces oxygen in the packaging, further reducing the chances of oxidation and rancidity. For example, many snack food packages are filled with nitrogen gas to maintain freshness.

**Summary:**
- Rancidity is the oxidation of fats and oils in food, resulting in bad smells and tastes.
- To prevent rancidity, food should be stored in airtight containers and can also be kept in the refrigerator or packaged with inert gases like nitrogen.

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