Post Harvest Management- ICAR JRF/SRF 2024

• Assertion (A) is True: Lycopene bioavailability from processed or thermally cooked tomato products (tomato paste, puree, sauce) is significantly higher ($2 - 3\times$) than from raw fresh tomatoes.
• Reason (R) is False: Thermal processing induces isomerization of all-trans lycopene into cis-isomers.
• Cis-isomers of lycopene are MORE bioavailable than all-trans isomers because cis-isomers possess a bent conformation that reduces aggregation, enhances solubility in oil, and facilitates incorporation into bile acid mixed micelles for intestinal absorption.
• Therefore, the assertion that "all trans form are more bioavailable than cis isomers" is scientifically false.
• Conclusion: Assertion (A) is true but Reason (R) is false (Option 3).

Correct option: (3) (A) is true but (R) is false

• Duo-Trio Sensory Evaluation Test:
• standardized difference testing method in sensory analysis (ISO 10399).
• Sample Protocol: The panelist receives three samples in total:

• One identified and labeled Reference sample ($R$)
• Two coded unknown samples (one of which is identical to $R$, and the other is the test sample)
  • The evaluator tastes the reference first and identifies which of the two coded samples matches the reference.

• Correct Option: Option 2 (Three).

• Water Quality for Fruit and Vegetable Canning:
• Water hardness is caused by dissolved calcium and magnesium bicarbonates, sulfates, and chlorides.
• Permitted Hardness Limit: Should not exceed $85\text{ ppm}$ (or $85\text{ mg/L}$ as $\text{CaCO}_3$), equivalent to 5 grains per US gallon (soft to moderately soft water).
• Excessive hardness ($\gt 85-100\text{ ppm}$) results in calcium crosslinking with pectin in canned legumes (peas, beans), causing unnatural toughening and forming cloudy white precipitates in brine or syrup.
• Correct Option: Option 2 (85 ppm).