Microbial Growth in Ground Beef During Different Methods of Thawing.

Consumer safety has now become a pressing issue with recent illnesses and food recalls due to elevated microbiological contamination of a variety of different foods. Although there are many different steps in the handling and processing continuum that expose the food supply to potential microbial exposure and contamination, consumers can limit their risk for food-borne illness by practicing safe food handling practices in their homes. In this study, we examined several commonly used thawing methods and their impact on microbial growth. The purpose of this study was to evaluate the influence of different thawing methods on microbial growth in ground beef. Microbial growth was evaluated during a six-hour thaw period using three different thawing methods: refrigerator, room temperature, and standing water bath. Beef maintained in the freezer was used as a control. Bacterial counts per gram of beef were determined at one-hour intervals using a viable count method. The least amount of bacterial growth occurred when beef was thawed in the refrigerator while bacterial growth occurred more rapidly in beef thawed at room temperature or in a standing water bath. After six hours, beef thawed in a standing water bath had the greatest bacterial count, 1.5 x 104 bacteria per gram of beef. This was 1.75 and 3.89 times greater than the microbial counts in beef samples thawed at room temperature or the refrigerator, respectively.