Cabedo L, Sofos J N, Smith G C
Department of Animal Sciences, Colorado State University, Fort Collins 80523-1171, USA.
J Food Prot. 1998 Jan;61(1):36-40. doi: 10.4315/0362-028x-61.1.36.
A study was designed to determine populations of aerobic bacteria, coliforms, sorbitol-negative bacteria, and Listeria monocytogenes during display at 4 and 12 degrees C of ground beef patties made with meat from animals fed diets supplemented daily (for 100 days) with 0, 1,000, or 2,000 IU of vitamin E. The patties (113.5 g) were either left uninoculated or were inoculated with Escherichia coli O157:H7 or L. monocytogenes and were tray-overwrapped and stored (at 4 or 12 degrees C for 8 to 10 or 4 to 6 days, respectively) while being continuously exposed to fluorescent light in a display setting. Patties were visually evaluated for overall appearance (based on color and/or discoloration) twice a day and analyzed for microbiological counts at 2-day intervals during display at 4 degrees C and at 0, 1, 2, 3, 4, and 6 days during display at 12 degrees C. Use of beef from animals fed supplemental vitamin E ("high-vitamin E beef") resulted in ground beef patties which, when stored at 4 degrees C, maintained visually acceptable color longer than did patties made from control beef (from animals not fed supplemental vitamin E), but effects on microbial growth were less pronounced. In general, use of high-vitamin E beef versus control beef in patty manufacture had no major effect on populations of aerobic bacteria, coliforms, sorbitol-negative bacteria, or L. monocytogenes in ground beef patties displayed at 4 or 12 degrees C. Listeria monocytogenes multiplied at 12 degrees C, but growth was similar among ground beef patties made from high-vitamin E beef versus control beef. Overall, changes in bacterial populations were similar in ground beef patties derived from meat from animals with or without added vitamin E in their diets, but control ground beef became visually unacceptable sooner.
一项研究旨在确定用每日（持续100天）补充0、1000或2000国际单位维生素E的动物肉制成的牛肉饼在4℃和12℃展示期间的需氧菌、大肠菌群、山梨醇阴性菌和单核细胞增生李斯特氏菌的数量。将肉饼（113.5克）要么不接种，要么接种大肠杆菌O157:H7或单核细胞增生李斯特氏菌，然后用托盘包装并储存（分别在4℃或12℃下储存8至10天或4至6天），同时在展示环境中持续暴露于荧光灯下。每天对肉饼的整体外观（基于颜色和/或变色）进行两次视觉评估，并在4℃展示期间每隔2天以及在12℃展示期间的第0、1、2、3、4和6天对微生物数量进行分析。使用来自补充维生素E的动物的牛肉（“高维生素E牛肉”）制成的牛肉饼，在4℃储存时，其外观颜色在视觉上比对照牛肉（来自未补充维生素E的动物）制成的肉饼保持可接受的时间更长，但对微生物生长的影响不太明显。一般来说，在肉饼制作中使用高维生素E牛肉与对照牛肉相比，对在第4℃或12℃展示的牛肉饼中的需氧菌、大肠菌群、山梨醇阴性菌或单核细胞增生李斯特氏菌数量没有重大影响。单核细胞增生李斯特氏菌在12℃下会繁殖，但由高维生素E牛肉制成的牛肉饼与对照牛肉制成的牛肉饼之间的生长情况相似。总体而言，日粮中添加或不添加维生素E的动物的肉制成的牛肉饼中细菌数量的变化相似，但对照牛肉饼在视觉上更快变得不可接受。
