Korkeala H, Alanko T, Mäkelä P, Lindroth S
Department of Food and Environmental Hygiene, College of Veterinary Medicine, Helsinki, Finland.
Int J Food Microbiol. 1989 Nov;9(3):237-47. doi: 10.1016/0168-1605(89)90093-7.
Microbiological and sensory changes in 313 vacuum-packed cooked ring sausages from 28 different production runs and stored at 2, 4, 8 or 12 degrees C were monitored as a function of time. The sensory scores started to decrease at a level of approx. 10(7) lactobacilli/g. The judges began considering the samples unfit for human consumption when the lactobacilli counts were between 10(7) and 10(8) cfu/g; above a level of 10(8) cfu/g most of the samples were deemed unfit. At 2 degrees C, however, spoilage did not always seem to be microbiological, and four out of six different production runs were deemed unfit without any marked increase in microbial counts. In such cases, the judges described the sensory defects as a 'musty' rather than a sour aroma and taste. The sausages were deemed unfit when the lactobacilli were in a stationary growth phase which was considerably later than the point when the bacterial counts exceeded 10(7) cfu/g. The mean length of this delay was 30, 19, 16 and 7 days at 2, 4, 8 and 12 degrees C, respectively. The average shelf-lives were 55, 43, 29 and 17 days at 2, 4, 8 and 12 degrees C, respectively. The dependence of shelf-life on temperature can be formulated as follows: Shelf-life = 10(1.835 - 0.048 X temperature) The maximal shelf-life of this product, including nonmicrobiological spoilage, is assessed as approx. 10-11 weeks. A lactobacilli count greater than 10(7) cfu/g indicates that either the spoilage process has started or the product is already spoiled. When the lactobacilli count exceeds 10(8) cfu/g it is highly probable that the sausage sample is unacceptable.
对来自28个不同生产批次、分别贮藏于2℃、4℃、8℃或12℃的313根真空包装熟环形香肠的微生物和感官变化随时间进行了监测。感官评分在约10⁷ 个乳酸杆菌/克水平时开始下降。当乳酸杆菌计数在10⁷至10⁸ cfu/克之间时，评委开始认为样品不适于人类食用；高于10⁸ cfu/克时，大多数样品被认为不适于食用。然而，在2℃时，变质似乎并不总是由微生物引起的，六个不同生产批次中有四个在微生物计数没有明显增加的情况下被认为不适于食用。在这种情况下，评委将感官缺陷描述为“发霉”气味而非酸味，且味道不佳。当乳酸杆菌处于稳定生长期时，香肠被认为不适于食用，这比细菌计数超过10⁷ cfu/克的时间要晚得多。在2℃、4℃、8℃和12℃时，这种延迟的平均时长分别为30天、19天、16天和7天。在2℃、4℃、8℃和12℃时，平均货架期分别为55天、43天、29天和17天。货架期与温度的依赖关系可表述如下：货架期 = 10⁽¹·⁸³⁵⁻⁰·⁰⁴⁸×温度⁾ 该产品的最长货架期，包括非微生物变质，估计约为10 - 11周。乳酸杆菌计数大于10⁷ cfu/克表明变质过程已经开始或产品已经变质。当乳酸杆菌计数超过10⁸ cfu/克时，香肠样品极有可能不可接受。
