Paweena Rattanasena
Faculty of Technology, Mahasarakham University
Prapassorn Bussaman
Faculty of Technology, Mahasarakham University
Processing of rice grains into pre-germinated brown rice and pre-germinated rough rice are traditional Thai methods that have been used to increase the nutritional value, improve the texture and increase bioactive compounds of rice grains. In this study, grains of sticky rice, jasmine rice, purple sticky rice and red hawn rice grains were processed into pre-germinated brown rice and pre-germinated rough rice and extracted using methanol, ethanol and distilled water.
Pre-germination of rice grains can increase the percentage of extraction yield to be higher than those without pre-germination. Moreover, the methanol and ethanol extracts of rice varieties with pigments (purple sticky rice and red hawn rice) tended to have antioxidant activities measured by DPPH radical scavenging assay and levels of total phenolic compounds higher than those obtained from rice varieties without pigments and also those using water as a solvent. Pre-germination of rice grains however did not have much effect on antioxidant activities and total phenolic compounds of their extracts. Nonetheless, processing of grains into pre-germinated rough rice was shown to increase the significant levels of γ aminobutyric acid (GABA) in the rice grains. The data from this study could be beneficial for the future development of pre-germinated brown rice and pre-germinated rough rice products for therapeutic and cosmetic purposes.
(Presented in the 2012 Asian Food Heritage Forum: Harmonizing Culture , Technology and Industry, 20-21 August 2012, Imperial Queen’s Park Hotel, Bangkok, organized by Institute of Thai Studies, Institute of Asian Studies, Faculty of Fine and Applied Arts, Chulalongkorn University, Chinese Dietary Culture Institute, Zhejiang Gongshang University, and Ministry of Culture, Thailand)