Question

The enzyme used in isomerization of corn starch during the making of High Fructose Corn Syrup is/are:
(A). Alpha-amylase
(B). Glucoamylase
(C). Glucose isomerase
Choose the most appropriate answer from the options given below:

• A. (A) and (B) only
• B. (B) and (C) only
• C. (B) only
• D. (A), (B) and (C)

Hint:

Remember the HFCS enzyme chain: 1. \textbf{Alpha-amylase} cuts the big starch chains (liquefaction). 2. \textbf{Glucoamylase} cuts the small chains into glucose (saccharification). 3. \textbf{Glucose Isomerase} converts glucose to fructose (isomerization).

Answer 1

The Correct Option is D

Step 1: Concept Overview:
High Fructose Corn Syrup (HFCS) production from corn starch is an enzymatic process. Starch is broken down into glucose, and a portion of the glucose is converted to fructose.
Step 3: Enzyme Details:
The process utilizes three key enzymes:
1. (A) Alpha-amylase: Used in liquefaction, the first step. It breaks down long-chain starch into smaller dextrins.
2. (B) Glucoamylase: Used in saccharification, the second step. It breaks down dextrins into glucose, resulting in glucose syrup.
3. (C) Glucose isomerase: The third enzyme. It converts a portion of glucose into fructose during isomerization. Fructose's higher sweetness results in "high fructose" syrup.
The question asks about enzymes used "during the making" of HFCS, implying the entire process. Thus, all three enzymes are involved.
Clarification: The original question is slightly ambiguous. It mentions "isomerization of corn starch," which is specifically done by glucose isomerase (C). However, it also mentions "during the making of High Fructose Corn Syrup," encompassing the whole process. Based on the available options, the question is interpreted as referring to the entire manufacturing process. If the question ONLY referred to isomerization, the answer would be (C). Since (A), (B), and (C) is an option, the intention is to cover the complete process.
Step 4: Conclusion:
HFCS production from corn starch requires alpha-amylase, glucoamylase, and glucose isomerase. Therefore, option (D) is the most comprehensive answer.