Poelma P L, Romero A, Wilson C R, Andrews W H
J Assoc Off Anal Chem. 1976 Jul;59(4):731-33.
A method for detecting Salmonella in dried active yeast was subjected to collaborative study. This method employs trypticase soy broth as the pre-enrichment medium, a sample-to-broth ratio of 1:10, and subsequent transfers to lauryl sulfate tryptose broth and tetrathionate before streaking onto selective agars. Each collaborating analyst received ten 25 g samples of dried active yeast. Duplicate 25 g samples were each inoculated with Salmonella oranienburg at a low level (28 cells) and a high level (107 cells). Similarly, duplicate 25 g samples were each inoculated with S. senftenberg at a low level (30 cells) and a high level (114 cells). The remaining 2 of 10 samples were not inoculated. Results from 12 of 13 collaborators were evaluated. Only 2 (8.2%) of the 24 low level S. oranienburg samples were reported incorrectly as negative. Twelve of the analysts detected S. senftenberg at both levels and S. oranienburg at the high level in the inoculated samples. Results from 12 collaborators used in the final evaluation show that 117 of 119 (98.3%) collaborative determinations are in agreement. The official final action method for the detection and identification of Salmonella, 46.013-46.026, has been revised official first action to include applicability to dried active yeast.
对一种检测干活性酵母中沙门氏菌的方法进行了协同研究。该方法采用胰蛋白酶大豆肉汤作为预增菌培养基，样品与肉汤的比例为1:10，随后转移至月桂基硫酸盐胰蛋白胨肉汤和四硫磺酸盐肉汤中，然后划线接种到选择性琼脂上。每位参与协同研究的分析人员收到10个25克的干活性酵母样品。将25克的重复样品分别接种低水平（28个细胞）和高水平（10⁷个细胞）的奥兰治堡沙门氏菌。同样，将25克的重复样品分别接种低水平（30个细胞）和高水平（114个细胞）的森夫滕贝格沙门氏菌。10个样品中的其余2个未接种。对13位协同研究者中的12位的结果进行了评估。24个低水平奥兰治堡沙门氏菌样品中只有2个（8.2%）被错误地报告为阴性。12位分析人员在接种样品中检测到了高水平的森夫滕贝格沙门氏菌和奥兰治堡沙门氏菌。用于最终评估的12位协同研究者的结果表明，119次协同测定中有117次（98.3%）结果一致。沙门氏菌检测和鉴定的官方最终行动方法46.013 - 46.026已修订为官方首次行动方法，以包括适用于干活性酵母。
