The $F$-value (thermal death time or process lethality) is the total heating time in minutes at a specified reference temperature required to achieve a specified overall reduction ratio (such as $12D$ reduction) in a target microbial population. The $D$-value is specifically the time for a single decimal ($90\%$) reduction. Option analysis: (A) $D$-value is for one log ($90\%$) reduction only. (B) $F$-value represents the total process time to achieve a specified overall reduction ratio. (C) $Z$-value is the temperature increase required to change $D$-value by a factor of $10$. (D) $Q_{10}$ is temperature coefficient.

Blanching is a mild thermal pre-treatment applied to fruits and vegetables before canning, freezing, or drying. Its primary purposes are: inactivating heat-resistant quality-degrading enzymes like peroxidase and catalase (A), expelling tissue gases and softening/shrinking vegetables to facilitate container filling (B), and washing away surface dust and reducing initial microbial load (C). It is NOT designed for complete destruction of bacterial pathogens or spores (D), which requires commercial sterilization or pasteurization. Option analysis: (A) Includes incorrect statement (D). (B) (A), (B) and (C) only is the correct answer. (C) Omits microbial reduction (C). (D) Includes incorrect statement (D).

During hydrothermal parboiling (soaking and steaming of paddy), the starch granules gelatinize and expand into internal cracks, fissures, and chalky zones, fusing the endosperm into a hard, vitreous, uniform mass upon drying. This gelatinized structure imparts high mechanical strength and drastically reduces grain breakage during milling. Option analysis: (A) Oil migration affects bran oil yield, not breakage. (B) Parboiled rice becomes translucent, not opaque. (C) Husk loosening aids dehulling, not kernel hardness. (D) Gelatinization of starch heals internal fissures and hardens the kernel.