The hydrothermal parboiling process of paddy consists of soaking, steaming, and drying. The primary fundamental transformation responsible for the marked increase in head rice yield during subsequent milling is:
Options:
(A) Complete gelatinization of endosperm starch, which fuses internal micro-cracks and fissures.
(B) Fermentation of the outer husk layer by lactic acid bacteria.
(C) Sublimation of endosperm lipids into the husk.
(D) Thermal crystallization of amorphous cellulose fibers.
Answer Key:
A
Step-by-Step Solution & Explanation
During the steaming stage of parboiling, moisture and steam heat gelatinize starch granules in the rice endosperm. As gelatinized starch retrogrades and hardens during subsequent controlled drying, it heals internal chalkiness, checks, and micro-fissures caused by rapid pre-harvest drying, making the kernel mechanically robust and significantly reducing breakage (increasing head rice yield) in rubber-roll shellers and polishers.