Abstract:

This paper reported decontaminative effects of irradiation on the soy protein flour quality,including main nutrient components,sensitivity of urea enzyme and sensory index.The results show that the irradiation treatment is very effective in eliminating microorganism in soy protein flour.The higher the dose was,the more microorganisms were eliminated.At least 53% microorganisms were eliminated at 2.0 kGy irradiation.Eliminating ratios of 95%,97% and 100% were obtained at applied doses 4.0,6.0 and 8.0 kGy,respectively.The content of protein,crude fiber,total sugar and amino acid(except Leu) and urea enzyme would not vary much in the ranged of 2 to 8kGy.But the content of crude fat and lecithin in irradiated soy protein flour is significant different(at 0.01 level),and the content of isoflavone significantly decreased(at 0.05 level).Irradiation will not change the sensory index of soy protein flour much when irradiation dose is lower than 6.0 kGy.It was concluded that the optimal dose for bacteria decontamination of soy protein flour is in the range of 3.0～5.0 kGy for the sake of various quality factors.

Key words: soy protein flour, irradiation decontamination, dose, nutritional components

摘要：

研究了60Coγ射线辐照大豆蛋白粉的杀菌效果与对大豆蛋白粉的主要营养成分、尿素酶(脲酶)活性以及感官品质的影响。结果表明,2.0kGy辐照对大豆蛋白粉中菌落总数、大肠菌群的杀菌率达70%,对霉菌的杀菌率达53%;4.0kGy辐照杀菌率达95%;经6.0kGy辐照处理后,杀菌率达到97%以上,辐照的大豆蛋白粉样品中微生物指标均达到食品卫生国家标准;8.0kGy辐照杀菌率达到100%。与对照相比,剂量为2.0~8.0kGy的辐照对大豆蛋白粉中蛋白质、粗纤维、总糖、氨基酸(除Leu)含量的影响不明显;而粗脂肪及卵磷脂的含量有极显著变化(P<0.01),尤其是卵磷脂的含量显著增加,异黄酮的含量则显著降低(P<0.05);辐照对大豆蛋白粉中尿素酶活性没有显著影响;6.0kGy以下剂量辐照对大豆蛋白粉色泽、气味、口感无明显改变。综合试验结果,确定了大豆蛋白粉辐照杀菌的适宜工艺剂量范围为3.0~5.0kGy。

关键词: 大豆蛋白粉;;辐照杀菌;;剂量;;营养成分