Following a request from the European Commission, the EFSA Panel on Biological Hazards was asked to deliver a scientific opinion on the transportation of carcasses and the production of minced meat. Transportation was dealt with in part 1 of this opinion. This document (part 2) deals with minced meat and has two objectives: (1) to assess the impact of the storage time of fresh meat intended for the production of minced meat on the risk linked to the microbiological growth of potentially harmful microorganisms; and (2) to recommend, if appropriate, in relation to such risk, maximum times of storage of fresh meat intended for the production of minced meat
Regulation (EC) 853/2004 requires that carcasses are immediately chilled after post-mortem inspection to ensure that the temperature throughout the meat is not more than 7 °C in the case of meat and not more than 3 °C for offal. Minced meat must be prepared from animals other than poultry within no more than 6 days after slaughter with the exception of boned, vacuum-packed beef and veal, for which minced meat may be prepared up to 15 days post slaughter. Poultry meat must be chilled to not more than 4 °C as soon as possible after post-mortem inspection and the maximum storage time between slaughter and the production of minced meat must be no more than 3 days.
The requirement for maximum storage times between slaughter and the production of minced meat is creating problems for the meat industry. For example, beef carcasses may be matured in slaughterhouse chillers for periods in excess of those currently permitted under Regulation (EC) 853/2004. This opinion investigates the possibility of extending the duration between slaughter and minced meat preparation without increasing the growth of potentially harmful bacteria; more specifically the impact of the time and temperature of storage (between slaughter and the preparation of minced meat) of fresh beef, pork, lamb and poultry on the growth of potentially harmful microorganisms. Target pathogens were selected based on their occurrence on red meat or poultry, and/or their ability to grow at chilled temperatures and included Salmonella spp., verocytotoxigenic Escherichia coli (VTEC), Listeria monocytogenes and Yersinia enterocolitica. Parasitic and viral pathogens do not grow on fresh meat and were therefore excluded. Campylobacter spp. pathogenic for humans, although prevalent on poultry carcasses, were also excluded as these bacteria do not usually grow outside of their host and never at temperatures below 30 °C.
The available data on growth of the relevant pathogens in the different meats during storage at different temperatures are limited and could not be used for a systematic approach for addressing the TORs. Instead, microbial growth models were used to predict pathogen growth potential on the meat surface during the storage period between slaughter and minced meat preparation using the most favourable conditions of pH and aw (water activity). Moreover, a lag phase before growth commenced was assumed to be absent and inactivation during storage and competition from other microorganisms were not considered. Thus, the predicted growth potential related to ideal conditions and represents a worst case scenario. To assess the impact of the time of storage of fresh red meat intended for the production of minced meat on the risk linked to microbiological growth of potentially harmful microorganisms, the growth potential of Salmonella spp., VTEC, L. monocytogenes and Y. enterocolitica was estimated at 7 °C for 5 days (baseline scenario 1) and 14 days (baseline scenario 2) and for an extended period using predictive models. These parameters were selected based on current legislation which states that a maximum temperature of 7 °C should be maintained and the maximum time between slaughter and minced meat preparation should be 6 or 15 days in the case of boned vacuum-packed meat. Allowing for carcass chilling, which requires on average 24 hours, this leaves 5 and 14 days, respectively, before the production of minced meat. To assess the impact of storage time of poultry meat on the growth potential of pathogenic microorganisms, the growth of L. monocytogenes and Y. enterocolitica was predicted during storage at 4 °C for 3 days (baseline scenario 3). Neither Salmonella spp. nor VTEC will grow at this temperature. This was based on current legislation which mandates a maximum storage temperature at 4 °C and a maximum storage time of 3 days between slaughter and mincing. As poultry carcass chilling requires only approximately 2 hours this did not significantly reduce the 3 days storage time. In order to recommend maximum times of storage of fresh meat intended for the production of minced meat, pathogen growth potential was predicted using different time-temperature scenarios and compared with that obtained using baseline scenario 1 and 2 (red meat) and baseline scenario 3 (poultry meat). Combinations of extra days at temperatures of 1 °C to 6 °C were evaluated and those that resulted in equivalent growth potential to that obtained with the relevant baseline scenarios were considered to represent equivalent risk.
As an example, a cautionary worst-case approach was applied based on the pathogen and the lactic acid model giving the shortest maximum storage times that resulted in equivalent growth potential. The predicted shortest equivalent time for storage of red meat at each temperature, was 12, 11, 9, 8, 7 and 6 days at 1, 2, 3, 4, 5 and 6 °C, respectively before growth equivalent to that obtained at 7 °C after 6 days (baseline scenario 1) would occur. In vacuum-packed red meat, growth equivalent to that obtained at 7 °C after 15 days (baseline scenario 2) was predicted after 48, 39, 31, 25, 20 and 17 days at 1, 2, 3, 4, 5 and 6 °C, respectively. For poultry, growth equivalent to that obtained at 4 °C after 3 days (baseline scenario 3) was obtained after 5, 4 and 3 days at 1, 2 and 3 °C, respectively. It was concluded that the storage times can be extended while maintaining equivalent risk by decreasing the storage temperature. The impact of spoilage on maximum storage times was not considered.