The similarity in GABA levels at 24 h duration in comparing modern rice varieties to landrace and purple rice varieties showed the significant usefulness of the unimproved local rice varieties in processing GBR. In particular, a purple rice variety, Kum Doi Saket, not only accumulated high GABA content but also possessed the purple pigment of anthocyanidin (cyanidin-3-glucoside and peonidin-3-glucoside).