Short germination and debranning affect bioactive compounds and pasting properties of rice genotypes

Abstract

Germination is a natural metabolic process widely used to modify sensory properties and nutritional aspects. Rice containing high amylose content has a larger germ and, consequently, could accumulate higher γ-aminobutyric acid (GABA) levels in this portion. This study aimed to evaluate the effect of short germination and debranning on α-amylase activity, pasting properties, phytochemicals, and amino acid profile of genotypes with distinct amylose content. The results of the falling number showed that BRS Formoso (high amylose) presented the highest value (>1000 s), indicating no activity of α-amylase and higher retrogradation (3793–3593 cP), whereas Mochi (waxy genotype) demonstrated the lowest retrogradation (maximum of 241 cP). Short germination increased L-glutamic acid and GABA contents in all genotypes, but debranning decreased these compounds. Short-time germination led to an expressive increase in umami amino acids, mainly in BRS Guaporé and Mochi, which also showed high levels of proline in both brown and polished grains. Novelty impact statement Short germination (<24 h) did not increase the α-amylase activity High amylose content impacted pasting properties and GABA synthesis Reduction of γ-oryzanol and γ-tocotrienol is more pronounced in polished rices