核桃粉辐照杀菌剂量

以核桃粉为材料,通过研究辐照对核桃粉中各营养成分及感官质量的影响,确定了核桃粉辐照杀菌剂量.结果表明:辐照前2种供试核桃粉中的菌落总数均超过了固体饮料国家标准中对菌落总数的限值;辐照对核桃粉的杀菌效果显著,本试验范围内2.6 kGy的辐照即日可使核桃粉中菌落总数的含量符合国家标准的要求,且当辐照剂量为8.7 kGy时2种核桃粉中的耐热芽孢杆菌可以被完全杀灭;2种核桃粉中菌落总数的D_(10)值分别为2.79kGy与2.99 kGy,耐热芽孢杆菌的D_(10)值分别为3.32 kGy与3.48 kGy;辐照处理对核桃粉中氨基酸、水分和灰分含量及感官品质的影响都不显著,对锰、钙、铁的含量有一定的影响,辐照剂量超过5.0 kGy时,V_B_2含量超过对照中的含量.综合试验结果,确定核桃粉辐照杀菌的适宜剂量为4-8 kGy.

Irradiation Dose for Decontamination of Walnut Powder

Irradiation dose for decontamination was fixed by studying on effect of irradiation on contents of nutrient components and sensory quality using two kinds of walnut powder. The results show that, the number of total bacteria in two kinds of walnut powder unirradiated were both beyond state hygiene standard of solid drink ,though the numbers of coliform bacteria and mould in unirradiated and irradiated samples were all within standard ; Irradiation dose changing from 2.6～8.7 kGy,it was enough for 2.6 kGy to drop the number of total bacteria to less than 10~3 CFU/g,meanwhile,and 8.7 kGy to drop the number of alicyclobacillus acidoterrestris to none. The D_(10) values of total bacteria in 2 kinds of walnut powder were 2. 79 kGy and 2. 99 kGy while those of alicyclobacillus acidoterrestris were 3. 32 kGy and 3.48 kGy. Within this dose range, neither the contents of amino acids, moisture and ash nor sensory quality was significantly changed, but the contents of Mn,Ca,Fe were changed significantly,and content of V_B_2 was more than that of CK when irradiation dose was beyond 5.0 kGy. Therefore,the appropriate irradiation dose range for decontamination of walnut powder was 4～8 kGy.