An overall concept for a generic model to predict the remaining shelf life of meat in different steps of the supply chain was developed. It consists of three models: a shelf life model, an inter-organisational cold chain model and a temperature mapping model that includes a heat transfer model. In this concept, shelf life is predicted based on the growth of Pseudomonas sp., taking into account organisational structure, inspection scheme, technical circumstances and temperature conditions in different supply chains. Whereas the shelf life model is almost complete, further work is required to develop the two other models.

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Storage tests were conducted to identify and compare factors influencing the growth of Pseudomonas spp. as specific spoilage organism on fresh pork and poultry. Besides the extrinsic factor, temperature, the intrinsic factors, pH‐value, aw‐value, Warner‐Bratzler shear force (WBSF), d‐glucose, L‐lactic acid, fat and protein content were analyzed. The growth of Pseudomonas spp. was clearly dependent on temperature, with faster growth at higher temperatures. Furthermore, growth was faster on fresh poultry than on fresh pork resulting in shorter shelf lives at constant temperatures from 2 to 15C. Almost all of the investigated intrinsic factors were significantly different (P < 0.05) for fresh pork and poultry (except aw‐value and L‐lactic acid). Pseudomonas spp. counts correlated significantly to all investigated parameters in pork except WBSF and to four of the seven parameters in poultry (pH, aw, d‐glucose, L‐lactic acid). However, magnitudes of these correlations were low, which indicates minor influences on shelf life. Practical Applications Early spoilage of fresh meat can lead to food waste and thereby economic losses as well as the loss of consumer confidence. Until now, there have been no previous detailed studies describing and comparing different intrinsic and extrinsic parameters and their influence on the growth of Pseudomonas spp. as specific spoilage organism in different types of meat. Understanding the main impact factors on shelf life of fresh pork and poultry is a prerequisite for the development of methods and tools for improving processes in meat supply chains. In particular, the results can serve as a basis for the development of mathematical models that can predict the shelf life and remaining shelf life of both meat types.

Summary In this study, the influence of fluctuations of the cold chain on the growth of Pseudomonas spp. on fresh pork and poultry and, therefore, their shelf life was evaluated. Thus, four storage trials were examined. In each trial, shelf life at the control scenario (4 °C, constant) was compared with shelf life at two dynamic scenarios including temperature shifts from 4 to 7 and to 15 °C, respectively. Overall, fresh pork and fresh poultry showed similar spoilage patterns at dynamic temperature conditions with remarkable reductions in the shelf life when short temperature upshifts occurred at the beginning of the storage. Reductions were up to 2 days (up to over 30%), although the storage time with an abusive temperature was <5% of the total storage time. As expected, scenarios with shifts to 15 °C led to higher shelf life reductions than scenarios with shifts to 7 °C for both meat types.