Affects of gamma irradiation on reduction of contaminated microorganisms and useful compounds in germinated brown rice sprout

This study was conducted to evaluate the growth inhibition effect of harmful microorganisms contaminated and changes of γ-aminobutyric acid (GABA) and β-sitosterol in germinated brown rice by gamma irradiation. Germinated brown rice sprouts with 3 mm length were separated and gamma-irradiated within the absorbed dose of 1, 2, 3, 4 or 5 kGy. Nonirradiated one was used as control. Gamma irradiation could reduce the numbers of Escherichia coli O157:H7, Salmonella typhimurium, Listeria monocytogenes, Staphylococus aureus and Bacillus cereus. Data from D10 values of microflora also indicated that gamma irradiation of 5 kGy could inhibit the growth of the harmful microorganisms. GABA was not affected by gamma irradiation, but β-sitosterol was affected and the content decreased. The results appeared that gamma irradiation can apply to eliminate the harmful microorganisms contaminated in germinated brown rice sprout for use as the ready-to-eat fresh cut vegetables