Enrichment of γ-aminobutyric acid based on rice heating and humidification technology

Abstract

Objective: This study aimed to improve the quality of brown rice. Methods: The content of γ-aminobutyric acid (GABA) and the activity of glutamate decarboxylase were used as indicators to study the effect of enrichment conditions on GABA content. Based on the optimal parameters, GABA content in each part of the grain was analyzed to reveal the migration law of GABA. Finally, the effect of the method on the quality of brown rice was analyzed and compared with the soaking method. Results: The highest GABA content was obtained when the water content of the raw material was 14.5% with the final moisture content of 20%, enrichment at 65 ℃ for 5 h. During the enrichment process, GABA was mainly generated in the bran layer and then migrated inward. The content of GABA in brown rice with different milling rates reached the peak at 5 h, but the migration rate tended to be stable after 4 h. The highest migration rate of GABA in endosperm was 87.1%. Compared with the soaking method, the brown rice enriched by the heating and humidifying method showed a yellower color, lower waist burst rate and softer cooked rice. Conclusion: The heating and humidification method is superior to the soaking method and can be used to prepare brown rice and white rice with high GABA content.

Keywords

• brown rice
• heating and humidifying
• gamma-aminobutyric acid
• glutamic acid decarboxylase
• migration rule