Survival of Yersinia enterocolitica during the Manufacture and Ripening of Mihalıç Cheese

Authors : Mehmet Kurtuluş Cem ŞEN, Seran TEMELLİ

Pages : 1029-1034

View : 20 | Download : 8

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The survival of Yersinia enterocolitica strain 0:9 was investigated during the manufacturing and ripening of Mihalıç cheese produced from raw milk. Mihalıç cheese was produced after inoculating 105 cfu/ml of Y. enterocolitica strain 0:9 into raw milk. All cheese samples were ripened at + 4 °C for 30 days in 18 to 22% of brine. Samples taken from raw milk, scalded and strained curd, and cheese on days 1, 3, 5, 8, 15 and 21 of the ripening process were analyzed for Y. enterocolitica, pH values and salt content. In raw milk, where initial inoculated Y. enterocolitica counts were 105 cfu/ml, counts were 1.5 x 106-7.1 x 106 cfu/g in scalded curd, 4.2 x 106-3.0 x 107 cfu/g in strained curd, 2.4 x 104-3.4 x 106 cfu/g on day 1, 3.8 x 103-2.5 x 105 cfu/g on day 3, and 9.2 x 102-4.0 x 104 cfu/g on day 5. During the ripening process, due to the decrease in pH values and the increase in salt content, Y. enterocolitica was diminished in the 1st batch on day 8, in the 3rd and 4th batches on day 15, and in the 2nd batch on day 21.
Keywords : Yersinia enterocolitica, cheese, ripening, viability