混合益生菌粉检验方法探讨

Discussion on Examination Method of Mixed Probiotic Powder

研究对比混合益生菌类产品中乳酸菌总数、双歧杆菌、嗜热链球菌的检测方法,提出了一种检出率和准确度更高的检测方法。传统国标检测方法,称取益生菌粉在均质袋中,通过拍打使益生菌产品在生理盐水中混匀,然后通过梯度稀释,在可计数梯度上,选用合适培养基,培养计数,计算益生菌活菌数。由于益生菌菌含量太高,均质袋拍打已无法使产品充分混匀,现通过研究在均质器选择、供试液制备时间控制、称样量的改变和提高稀释试管水体积准确度方面,来提高益生菌检测准确率。通过研究优化检测方法后,益生菌检验的原料及成品检出率提高100%;检验相对标准偏差小于15%,优化试管水后,改善前后对数值差值dlog≤0.25。该方法准确、稳定,适合测定混合益生菌粉中乳酸菌总数、双歧杆菌、嗜热链球菌的检测。

To compare the detection methods of total lactic acid bacteria,Bifidobacterium bacteria and Streptococcus thermophilus bacteria in mixed probiotic products,a detection method with higher detection rate and accuracy was proposed.In the traditional national standard test method,the probiotics powder is called in the homogenized bag,and the probiotics product is mixed in the physiological saline by beating,then the probiotics product is diluted by gradient,and the suitable medium is selected on the countable gradient,and the culture was counted,calculate viable count of probiotics.Because the content of probiotics is too high,the product can not be fully mixed by beating in homogenizing bag.In this paper,the selection of homogenizer,the control of preparation time of test solution,the change of sample size and the improvement of volume accuracy of dilution test tube water are studied,to improve the detection accuracy of probiotics.After optimizing the test method,the detection rate of probiotics was increased by 100%,the relative standard deviation was less than 15%,and dlog≤0.25 after optimizing the test tube water.The method was accurate,stable and suitable for the determination of total lactic acid bacteria,Bifidobacterium and Streptococcus thermophilus in mixed probiotic powder.