Why is the use of aspartame as an artificial sweetener limited to cold foods ?

Explanation

### Step-by-Step Solution:

1. **Understanding Aspartame**: Aspartame is an artificial sweetener commonly used in various food products. It is a low-calorie sweetener that is approximately 200 times sweeter than sucrose (table sugar).

2. **Chemical Composition**: Aspartame is made from two amino acids: aspartic acid and phenylalanine. These components contribute to its sweet flavor.

3. **Stability at Different Temperatures**: One of the key characteristics of aspartame is its stability. It is stable under certain conditions but becomes unstable when exposed to high temperatures.

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