Enrichment of GABA content in brown rice through heating and humidifying treatment: Quantification via TLC-ImageJ...

Gamma-aminobutyric acid (GABA) is a functional food ingredient for human health. This study aimed to investigate the enrichment and migration rule of GABA in rice by heating and humidifying treatment (HHT). The thin layer chromatography-ImageJ method (TLC-ImageJ) was developed for determining GABA. TLC-ImageJ demonstrated high accuracy and linearity, with a relative error of 5.00 %-11.16 % and an R² value of 0.9943. The highest GABA content was 258.03 mg/kg in paddy found at 65 °C, 20 % and 5 h. GABA was primarily produced in the germ and migrated inward during the enrichment process. The highest GABA content in paddy with different degrees of milling was observed at 6 h, but the mobility remained stable after 4 h, and the migration of GABA produced by the germ to endosperm reached 87.37 %. Conclusively, the HHT can produce GABA-enriched rice, while the TLC-ImageJ provided a rapid and accurate approach for quantitatively determining GABA content.