超微粉碎对脱脂糯小米米糠的抗氧化性和肠道益生性的影响

Effect of Ultrafine Comminution on Anti-oxidation Property and Prebiotic Function of Defatted Millet Bran

以重庆小米米糠为原料,采用脱脂和超微粉碎技术制备不同目数的脱脂小米米糠微粉,探讨超微粉碎对脱脂小米米糠的抗氧化性和肠道益生性的影响。随着微粉粒径的减小,总酚含量增加,DPPH清除率提高,还原力增强,说明超微粉碎使脱脂小米米糠粉的抗氧化性增强。肠道微生物发酵结果显示:添加脱脂小米米糠微粉的发酵液相对于阴性对照p H更低;随着超微粉碎程度的加深,脱脂小米米糠微粉对乳酸菌和双歧杆菌的增殖效果提高,而对大肠杆菌的增殖效果下降;与阴性对照组相比,添加微粉的发酵液中乙酸、丙酸、丁酸浓度显著升高,且添加>400目微粉的短链脂肪酸浓度最大。试验结果表明:超微粉碎能够促进脱脂小米米糠微粉对益生菌乳酸菌、双歧杆菌的增殖作用,减小其对大肠杆菌的增殖作用,并且超微粉碎程度越大,粒径越小,其益生作用越显著。

This experiment explored the influences of ultrafine comminution on the anti-oxidation properties and pre- biotic effect of defatted millet bran. The results were as follows： With particle size＇s decreasing, total phenolic content, DPPH-scavenging ability and reducing power had a certain degree of increase, this showed that the anti-oxidation prop- erty was enhanced. Besides, the fermented broth with defatted millet bran powder had a lower pH, a higher concentra- tion of short-chain fatty acid; With particle size＇s decreasing, the defatted millet bran powder had an increasingly active effect on the growth of Lactobacillus spp. and Bifidobacterium spp. but an increasingly negative influence on the growth of Escherichia spp. All of these suggested that ultrafine comminution improved the prebiotic effect of defatted millet bran, and the prebiotic effect was more pronounced with the decreasing of the particle size.