Use of predictive microbiology in meat hygiene regulatory activity

New Zealand is a supplier of refrigerated raw meat to world markets. To maintain this supply, from regulatory and commercial perspectives, production standards need to deliver products that are both hygienically adequate and commercially viable. A dynamic Temperature Function Integration (TFI) model, as a form of predictive microbiology, was used jointly by regulators and processors to develop justifiable criteria for the management of refrigeration during the production of hot and warm-boned meat, the post-slaughter handling of ovine carcasses and the handling of offals. Current processes operating according to accepted standards for Good Manufacturing Practice (GMP) were quantified in terms of TFI. The hygienic adequacy of new processes were similarly determined using the TFI model and compared to relevant GMP standards. From a regulatory perspective, the dynamic TFI model has provided a rapid and cost effective method of quantifying a temperature dependent process in terms of the potential for microbial proliferation. It has also produced a method for determining parameters for new or intended processes by comparing the potential for microbial proliferation with previously validated outputs, and has complemented traditional quantitative microbiology to provide a rapid, cost effective method of verifying that a process is performing according to design parameters. However, it could not be used to validate standards for processing in the absence of existing standards for GMP, or in the absence of microbial standards previously established using the principles of risk assessment.