Joosten Han, Bidlas Eva, Garofalo Nicole
Quality and Safety Department, Nestlé Research Centre, Vers-chez-les-Blanc, 1000 Lausanne, Switzerland.
Int J Food Microbiol. 2006 Jul 1;110(1):104-7. doi: 10.1016/j.ijfoodmicro.2006.01.036. Epub 2006 May 9.
The presence of large amounts of probiotic bacteria in a sample may interfere with the detection of undesirable microorganisms. To illustrate this, infant formula with various strains of probiotic bacteria and the corresponding probiotic culture powders and premixes were artificially contaminated with low levels of Salmonella. Recovery of Salmonella was generally very poor when the conventional pre-enrichment procedure using buffered peptone water (BPW) was applied. However, this problem was overcome by adding antimicrobial compounds to selectively suppress the growth and/or metabolic activity of the probiotic bacteria and increasing the buffering capacity of the pre-enrichment broth. It is recommended that these analytical constraints are already addressed during the development phase of new probiotic products.
样本中大量益生菌的存在可能会干扰不良微生物的检测。为了说明这一点，将含有各种益生菌菌株的婴儿配方奶粉以及相应的益生菌培养粉和预混料用低水平的沙门氏菌进行人工污染。当采用使用缓冲蛋白胨水（BPW）的传统预富集程序时，沙门氏菌的回收率通常非常低。然而，通过添加抗菌化合物以选择性地抑制益生菌的生长和/或代谢活性，并提高预富集肉汤的缓冲能力，这个问题得到了克服。建议在新益生菌产品的开发阶段就解决这些分析限制。
