Use of a temperature function integration technique to assess the hygienic adequacy of a beef carcass cooling process
ABSTRACT The hygienic performance of a commercial beef carcass cooling process was assessed by a temperature function integration technique. The times required for beef sides to cool to a deep temperature of 7°C indicated that the process accorded with currently accepted Good Manufacturing Practice. The potential proliferations ofEscherichia coli were calculated from 50 temperature histories obtained from the site on side surfaces that remained at the highest temperature for the longest periods. Criteria for defining the hygienic adequacy of carcass cooling processes based on estimatedE. coli proliferation are suggested from those data.
Article: Predicting the growth of Salmonella typhimurium on beef by using the temperature function integration technique.[show abstract] [hide abstract]
ABSTRACT: Lag and generation times for the growth of Salmonella typhimurium on sterile lean beef were modeled as functions of cooling time under various carcass-chilling scenarios. Gompertz growth models were fit to the log10 colony counts over time at each of six temperatures in the range of 15 to 40 degrees C. Lag and generation times were defined as the points at which the second and first derivatives, respectively, of each growth curve attained a maximum. Generation time and lag time parameters were modeled as functions of temperature by use of exponential-decay models. The models were applied to typical beef carcass-cooling scenarios to predict the potential growth of S. typhimurium during the cooling of beef. Validation studies indicated no significant difference between the observed and predicted bacterial populations on inoculated lean and fatty beef tissues cooled at either 6 or 9 degrees C/h.Applied and Environmental Microbiology 12/1992; 58(11):3482-7. · 3.83 Impact Factor
[show abstract] [hide abstract]
ABSTRACT: Because microorganisms are easily dispersed, display physiologic diversity, and tolerate extreme conditions, they are ubiquitous and may contaminate and grow in many food products. The behavior of microbial populations in foods (growth, survival, or death) is determined by the properties of the food (e.g., water activity and pH) and the storage conditions (e.g., temperature, relative humidity, and atmosphere). The effect of these properties can be predicted by mathematical models derived from quantitative studies on microbial populations. Temperature abuse is a major factor contributing to foodborne disease; monitoring temperature history during food processing, distribution, and storage is a simple, effective means to reduce the incidence of food poisoning. Interpretation of temperature profiles by computer programs based on predictive models allows informed decisions on the shelf life and safety of foods. In- or on-package temperature indicators require further development to accurately predict microbial behavior. We suggest a basis for a "universal" temperature indicator. This article emphasizes the need to combine kinetic and probability approaches to modeling and suggests a method to define the bacterial growth/no growth interface. Advances in controlling foodborne pathogens depend on understanding the pathogens' physiologic responses to growth constraints, including constraints conferring increased survival capacity.Emerging infectious diseases 3(4):541-9. · 6.17 Impact Factor