Question

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Per cent of moisture content expressed on dry basis can never be beyond 100%.
Reason R: On dry basis, moisture content of a sample is expressed with reference to total dry matter content of the sample.
In light of the above statements, choose the correct answer from the options given below

• A. Both A and R are true and R is the correct explanation of A
• B. Both A and R are true but R is NOT the correct explanation of A
• C. A is true but R is false
• D. A is false but R is true

Hint:

- Wet basis moisture content can never exceed 100% (as water mass cannot exceed total mass).
- Dry basis moisture content can theoretically range from 0% to infinity, meaning it can easily exceed 100% for high-moisture foods.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Moisture content (MC) in agricultural products can be expressed on two different bases:
- Wet Basis (\(MC_{wb}\)): Calculated relative to the total mass of the wet sample.
- Dry Basis (\(MC_{db}\)): Calculated relative to the mass of the dry solid matter in the sample.
Key Formula or Approach:
The mathematical definition of dry basis moisture content is:
\[ MC_{db} = \frac{M_w}{M_d} \times 100% \] Where: - \(M_w\) is the mass of water.
- \(M_d\) is the mass of dry matter.

Step 2: Detailed Explanation:
Let us evaluate both statements:
- Assertion A: "Per cent of moisture content expressed on dry basis can never be beyond 100%."
This statement is incorrect.
If a sample has a very high water content, the mass of water (\(M_w\)) can easily exceed the mass of dry solid matter (\(M_d\)).
For example, in fresh fruits or leafy vegetables, the water content can be 90% of the total mass.
- Let total mass = 100 g.
- Mass of water (\(M_w\)) = 90 g.
- Mass of dry matter (\(M_d\)) = 10 g.
The moisture content on a dry basis is:
\[ MC_{db} = \frac{90}{10} \times 100% = 900% \] This is much higher than 100%.
- Reason R: "On dry basis, moisture content of a sample is expressed with reference to total dry matter content of the sample."
This statement is correct, as shown by the formula \(MC_{db} = \frac{M_w}{M_d} \times 100%\), where the reference is the dry matter mass (\(M_d\)).
Therefore, Assertion A is false, but Reason R is true.

Step 3: Final Answer:
The correct option is (D).