which of the following enzymes is employed in the conversion of corn starch into fructose - rich corn syrup ?

Options

A. Amylases
B. Glucoamylasses
C. Glucoisomerases
D. All are correct

Answer

To determine which enzyme is employed in the conversion of corn starch into fructose-rich corn syrup, we can analyze the functions of the enzymes listed in the question.

### Step-by-Step Solution:

1. **Understand the Process**: The conversion of corn starch into fructose-rich corn syrup involves breaking down starch into simpler sugars and then converting those sugars into fructose.

2. **Identify the Enzymes**:
- **Amylase**: This enzyme hydrolyzes starch into maltose and dextrins. It is the first step in the breakdown of starch.
- **Glucoamylase**: This enzyme further breaks down dextrins and maltose into glucose. It is used to produce high glucose syrup.
- **Glucoisomerase**: This enzyme catalyzes the conversion of glucose into fructose. It is specifically used in the production of high fructose corn syrup.

3. **Determine the Key Enzyme**:
- While amylase and glucoamylase are important for breaking down starch into glucose, the enzyme that directly converts glucose into fructose is glucoisomerase. This step is crucial for producing fructose-rich corn syrup.

4. **Conclusion**: The enzyme that is primarily employed in the conversion of corn starch into fructose-rich corn syrup is **glucoisomerase**.

### Final Answer:
**Glucoisomerase** is the enzyme employed in the conversion of corn starch into fructose-rich corn syrup.

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