Question

Which of the methods is not commonly used to remove anti-nutritional factors from legumes? 
 

• A. Germination
• B. Boiling
• C. Drying
• D. Soaking & Milling

Hint:

To deactivate or remove anti-nutrients in legumes, you must either leach them out (soaking), heat-denature them (boiling), or enzymatically degrade them (germination). Simple drying does not achieve any of these effects.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Legumes contain various anti-nutritional factors (such as phytic acid, tannins, trypsin inhibitors, and lectins) that can reduce nutrient absorption and digestibility.
Various food processing methods are used to reduce or eliminate these compounds.
Detailed Explanation:
Let us analyze how each method affects anti-nutritional factors:
- Germination (A): Activates endogenous enzymes (like phytases) that break down phytic acid and reduce trypsin inhibitors, improving nutritional quality.
- Boiling (B): Thermal processing denatures heat-labile anti-nutritional factors, such as lectins (phytohemagglutinins) and protease inhibitors.
- Soaking & Milling (D): Soaking allows water-soluble anti-nutrients (like tannins and polyphenols) to leach out into the water. Milling removes the outer seed coat (husk), where many tannins and phytates are concentrated.
- Drying (C): Simple drying of legumes removes water but does not heat-denature proteins, leach out soluble compounds, or trigger enzymatic degradation.
Therefore, drying is not used to remove anti-nutritional factors.

Step 2: Final Answer:
Drying is the method not commonly used to remove anti-nutritional factors from legumes.