Chilled foods look set to benefit from a revolutionary new approach to shelf-life extension, thanks to collaborative UK research.
The Sustainable Shelf-Life Extension (SUSSLE) project subjects foods to much gentler heating processes to achieve the extended shelf-lives supermarkets expect, while retaining organoleptic qualities consumers demand.
SUSSLE gathered academics and industry experts to investigate the effects of heating spore-forming pathogens, particularly the potentially unsafe non-proteolytic Clostridium botulinum (C.botulinum).
"Collectively we took decisions that will no doubt impact positively on the safety of chilled prepared foods in the UK and internationally for years," said Dr Roy Betts, head of microbiology at Campden BRI.
The project aimed to reduce the temperature at which food is heat treated to stop pathogen growth. The Food Standards Agency (FSA) recommends 90°C for 10 minutes.
New thermal process
"To have an 11-day shelf-life you have to show you can control non-proteolytic C.botulinum by keeping food at a temperature of 90°C for 10 minutes," said Chilled Food Association (CFA) secretary general Kaarin Goodburn. "We wanted to challenge this rule, and have identified a new thermal process that can be applied to any fully cooked food, such as soups, sauces and Indian dinners."
The SUSSLE process gives a safe shelf-life at a temperature of between 70° and 90°C, improving the quality of the product since heating at a lower temperature reduces flavour loss. "We have found a way of increasing shelf-life and safety, giving manufacturers longer to sell," she added.
The £750,000 three-year project was funded by the CFA, Unilever, the Department for Environment, Food and Rural Affairs and the Biotechnology and Biological Sciences Research Council. Further research is planned.
The full results will remain confidential until April 2014.