Department of Food Science, The University of Naples Federico II, via Università 100, 80055 Portici, Italy.
Food Microbiol. 2010 Feb;27(1):137-43. doi: 10.1016/j.fm.2009.09.006. Epub 2009 Sep 17.
The aim of this study was to assess the microbial populations causing the spoilage of chilled beef during storage and to evaluate the effect of the use of an antimicrobial packaging for the meat storage. A nisin activated antimicrobial packaging was developed by using a nisin, HCL and EDTA solution and used for the storage of beef cuts at 1 degrees C. The common spoilage related microbial groups were monitored during the storage of beef in activated and non activated plastic bags by using selective media. The use of the antimicrobial packaging caused an overall significant reduction of viable counts of Gram positive bacteria such as carnobacteria, lactic acid bacteria and Brochotrix thermosphacta whose development was inhibited for at least 11 days of storage compared to the control. Moreover, a 1-3 log cycles reduction of enterobacteria was also registered between 22 and 32 days of storage. The microbiota was assessed at species level by using Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis of 16S rRNA gene of DNA extracted directly from meat and from bulk cells from selective media plates and showed that the species occurring within the targeted microbial groups did not change according to storage conditions. In conclusion, the use of the nisin activated packaging reduced the number of spoilage populations but did not affect the species diversity. Improved antimicrobial packaging is needed, possibly coupled with vacuum storage, to possibly achieve a simultaneous inhibition of more spoilage microbial groups and to preserve the microbiological quality of beef during chilled storage.
本研究旨在评估冷藏牛肉在储存过程中导致变质的微生物种群，并评估抗菌包装对肉类储存的影响。通过使用一种包含乳链菌肽、盐酸和 EDTA 的溶液，开发出一种尼生素激活的抗菌包装，并将其用于在 1 摄氏度下储存牛肉切片。通过使用选择性培养基，监测了牛肉在激活和非激活塑料袋中储存过程中常见的与变质相关的微生物群。与对照组相比，抗菌包装的使用导致革兰氏阳性菌（如肉杆菌、乳酸菌和嗜热解糖梭菌）的活菌数总体显著减少，其生长至少被抑制了 11 天。此外，在 22 至 32 天的储存期间，肠杆菌的数量也减少了 1-3 个对数循环。通过直接从肉中提取 DNA 的聚合酶链反应-变性梯度凝胶电泳（PCR-DGGE）分析和从选择性培养基平板的大块细胞中提取的 16S rRNA 基因评估微生物群，发现根据储存条件，目标微生物群中出现的物种没有变化。总之，使用尼生素激活包装可以减少变质种群的数量，但不会影响物种多样性。需要改进抗菌包装，可能需要与真空储存相结合，以同时抑制更多的变质微生物群，并在冷藏储存期间保持牛肉的微生物质量。
