Author
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Berry, Bradford |
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Submitted to: Journal of Food Safety
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/14/2001 Publication Date: N/A Citation: N/A Interpretive Summary: Because color in beef patties cooked to a constant temperature is an unreliable indicator of food safety, current advice to consumers is to "use a meat thermometer and cook patties until they reach 160 deg F." Since it is likely that the internal temperature in a patty may be different in various locations, it is generally believed that the thickest portion of the patty should be measured because it quite likely is the coolest portion. An infrared camera offers the possibility of instantaneously capturing the temperature variability in a predesignated area such as a cut surface of a cooked beef patty. This technology was used on patties cooked to 160 deg F from the frozen and thawed states. Temperature variability in excess of 35 deg F was often detected within cooked patties. It was also found that the temperature variation within the patties was more consistent when patties were cooked from the thawed rather than the frozen state. Thus, it is advisable to measure temperature in more than one location in patties cooked from the frozen state. Brown cooked color was observed in patties cooked from the thawed state, while pink and red were the colors observed in patties cooked from the frozen state. Color of cooked patties should not be used as an indicator of either temperature or food safety. Technical Abstract: Variation in internal temperature in sectioned cooked beef patties cooked from the frozen and thawed states was assessed immediately following cooking to 71C using infrared thermography. Visual and instrumental color measurements were also obtained. Temperature variation was considerable (often > 19C) within patties. Internal temperatures tended to be higher and dmore consistent across patty cut surfaces when patties were cooked from th thawed rather than the frozen state. This may be particularly due to the increase in thickness observed for patties cooked from the thawed state, while patties cooked frozen tended to shrink in thickness and distort in shape during cooking. As noted in previous studies, following cooking, thawed patties were brown, while frozen patties were pink and red. Future research will be necessary to determine the most accurate method of assessing temperature in beef patties as affected by processing, compositional and cooking differences. |
