不同等级米糠的品质评价

Quality Evaluation of Different Grades of Rice Bran

为探明稻谷碾白加工过程中各级米糠的成分差异,采用单因素试验方法,从米糠的营养成分、脂肪品质及微生物指标等方面对统糠、油糠及滑米糠的品质进行了测定和综合评价研究。结果表明:粗脂肪含量统糠最高,为16.1%;油糠次之,为15.4%;滑米糠最低,为10.5%。粗蛋白含量油糠最高,为13.84g/100g;滑米糠次之,为7.184g/100g;统糠最低,仅为5.429g/100g。滑米糠各营养成分较低,但淀粉含量最高,达50.71%;统糠和油糠的淀粉含量差异不大。统糠的脂肪酶活力、脂肪酸值、过氧化值及菌落总数相对很高,分别达17.69mg/g、327.93KOHmg/100g、0.017 9g/100g、6.5×106 CFU/g;油糠的膳食纤维、粗蛋白、维生素E及γ-谷维素含量较高,分别为17.9%、13.84g/100g、0.92mg/100g、0.271 2%;统糠微生物污染较重,易酸败,油糠和滑米糠综合品质较高。为了保证精深加工的米糠原料品质,应及早采取相应的贮藏措施。

To investigate the component differences of various grades of rice bran during the whitening processing, the determination and comprehensive assessment of the quality of tong bran, oil bran and sliding bran was conducted through the single factor experimental methods. The results showed that： the tong bran had the highest crude fat content（16.1%）, oil bran took the second place（15.4%）, and sliding bran was the lowest （10. 5%）. The oil bran had the highest crude protein content（13. 84 g/100 g）, followed by sliding rice bran（7. 184 g/100 g）, and tong bran content was the lowest, only 5. 429 g/100 g. The sliding bran had the lower nutritional components, but the highest starch content which reached 50.71%. The difference of starch content in tong bran and oil bran was little. The lipase activity, fatty acid value, peroxide value and the total colony number of tong bran were relatively high, which were 17.69 mg/g, 327.93 KOH mg/100 g, 0. 017 9 g/100 g, 6.5X106 CFU/g respectively. The dietary fiber, protein, high content of vitamin E and y-oryzanol of oil bran were higher, which reached 17.9%, 13.84 g/ 100 g, 0.92 mg/100 g and 0. 271 2% respectively. The microbial contamination for tong bran was more serious and easy to rancidity. The comprehensive quality of oil bran and sliding bran were higher. In order to guarantee the raw material quality of rice bran after the deep processing, the appropriate preservation measures for rice bran should be taken eariler.