Why is Temperature Control Important?
Temperature and time controls are important in preventing or slowing down the multiplication and survival of pathogenic bacteria. But failures in managing these critical controls are still a major cause of food poisoning outbreaks. Food business operators have a moral and legal duty to ensure validated time and temperature controls are in place and followed in practice. Poor risk perception for multiplication and survival of pathogenic bacteria by food handlers and management has led to fatalities, imprisonment and substantial fines. Two deaths in 2013 and 2016 involving food contaminated with Clostridium perfringens could have been avoided if appropriate cooling and reheating procedures were correctly followed. Cooling food down quickly restricts germination spore forming pathogens and thorough cooking destroys endotoxins that cause illness.
Chilled storage between 5OC - 8OC in most cases is an effective control measure, but problems in food safety can still happen. Listeria monocytogenes is psychotropic pathogen that can multiple at a temperature as low as -1.5OC and grow rates can double at temperatures above 5OC. Scombrotoxic poisoning is responsible for 65% of food poisoning in England. Poisoning occurs when histidine, an amino acid found in dark fleshed fish, converts to histamine due to spoilage. This can happen when fish is stored above 5OC. Correct chilled storage is a critical control point as the heat resistant toxins cannot be destroyed by cooking.
Cooking food at 75OC for 30 seconds or equivalent temperature and time combination destroys most pathogenic bacteria, but problems can arise between food safety and customer preference for less than thoroughly foods. There have been outbreaks of food poisoning involving undercooked burgers and chicken liver parfait. The consumption of undercooked burgers at concert venue led to an outbreak e-coli food poisoning that made twenty-two people ill. Investigators blamed inconsistent cooking practices and temperature monitoring. Public Health England also report in 2014 that 80% of large outbreaks of Campylobacter food poisoning involve chicken liver parfait.
There are ways to reduce the risk of serving less than thoroughly cooked foods. Sous vide cooks food in a plastic pouch at a very low temperature, but the process must be carefully controlled. Guidance produced by the Food Standards Agency states minimum core temperature of cooking vacuum packed foods is 60OC for 45 minutes. Weight of the product is also a critical factor in calculating the time to achieve the correct core temperature. Cooking foods below this time and temperature threshold should be validated through microbiological testing of the finished product.
There is no law against a restaurant serving pink burgers, but it must demonstrate additional controls to prepare and serve burgers safely. Proposed Food Standards Agency guidance for serving burger rare includes:
Time and temperature controls can reduce the risk of food poisoning if validated processes are followed and monitored. Problems arise where food handlers are not trained and perception of risk is low. Food can be served raw or lightly cooked where scientific evidence can prove the process if safe.
Percipio Training provides guidance on time and temperature controls on all its food safety and HACCP courses. We will make sure your team knows why temperature controls are important, and what happens when things go wrong. Contact us to find out more on how we can support your business.