Abstract
To identify optimal conditions of “GABA Enriching Equipment” for making GABA enriched high eating quality whiterice (GABA rice), we measured the GABA contents in whiterice and performed sensory evaluation and volatile compounds analysis of cooked rice, using the Hokkaido rice cultivar “Yumepirika”. Quantity of GABA included in GABA rice following a 3-hours enrichment had much about 10 times of normal whiterice at 11.4mg/100g of whiterice. Sensory and volatile analysis of cooked rice showed that GABA rice following a >4-hours enrichment process had distinctive “grassy and raw smells”. Therefore, we concluded that a 3-hours enrichment process was the most suitable for GABA rice. The stress relief effects of GABA rice in humans were investigated in a randomized, placebo-controlled, double-blind clinical trial.Thirty-nine adult subjects were enrolled in this study and were divided into the following two groups : GABA rice or placebo whiterice; 150g of whiterice was fed daily for eight weeks. VAS tests revealed that the mental condition and quality of sleep tended to improve by the intake of GABA rice. In addition, blood cortisol and adiponectin levels indicated that stress load tended to be lighten by GABA rice. In conclusion, the intake of GABA rice with a 3-hours enrichment process is effective for gently lightening the stress load.
