Gaya P, Medina M, Nuñez M
J Appl Bacteriol. 1987 Apr;62(4):321-6. doi: 10.1111/j.1365-2672.1987.tb04927.x.
Thirty-nine samples of freshly drawn ewes' milk collected at 13 farms, and 120 samples of raw ewes' milk collected on arrival at a dairy were examined. Farm samples had geometric mean counts of 4.4 X 10(2) Enterobacteriaceae/ml, 3.9 X 10(2) coliforms/ml and 2.0 X 10(2) faecal coliforms/ml, whereas the respective mean counts were 6.2 X 10(3)/ml, 5.4 X 10(3)/ml and 1.3 X 10(3)/ml for dairy samples. Salmonellas were not detected by enrichment procedures in any of the 159 samples examined. Escherichia coli (47.5% strains), Enterobacter cloacae (17.7%), Ent. agglomerans (11.3%), Hafnia alvei (6.5%) and Klebsiella oxytoca (6.0%) were the predominant species in 434 Enterobacteriaceae strains isolated from farm samples. Levels and species of Enterobacteriaceae found in the present work in raw ewes' milk imply a considerable risk of early blowing in cheese-making from unpasteurized milk.
对从13个农场采集的39份新鲜母羊乳样本以及在一家乳制品厂到货时采集的120份生羊乳样本进行了检测。农场样本中肠杆菌科的几何平均计数为4.4×10²/ml,大肠菌群为3.9×10²/ml,粪大肠菌群为2.0×10²/ml,而乳制品厂样本的相应平均计数分别为6.2×10³/ml、5.4×10³/ml和1.3×10³/ml。在所检测的159份样本中,通过富集程序均未检测到沙门氏菌。从农场样本中分离出的434株肠杆菌科菌株中,大肠杆菌(47.5%的菌株)、阴沟肠杆菌(17.7%)、成团肠杆菌(11.3%)、蜂房哈夫尼亚菌(6.5%)和产酸克雷伯菌(6.0%)是主要菌种。在本次研究中,生羊乳中发现的肠杆菌科水平和菌种表明,使用未杀菌的牛奶制作奶酪时存在早期产气的重大风险。