Moves away from thermal processing techniques and a reduction in the use of preservatives, such as salt, sugar and fat – together with other additives that prevent food spoilage – meant that processors were having to find alternative ways of ensuring food remained safe to eat, while not reducing shelf-life, speakers at Leatherhead Food Research’s (LFR’s) ‘Food safety day’ last week (May 23) reported.
Dr Helen Payne, a senior food safety adviser with LFR, said that the trend for milder processing and a move away from thermal treatments, as a way of raising product quality, were increasing food safety risks.
This had led to increased interest in food safety treatments such as high-pressure processing, ozone and pulsed field treatments, as well as the use of ultraviolet light and microwave ovens to kill off pathogens, she said.
‘Spoilage organism growth’
Payne added that the move away from using some preservatives and additives in favour of “clean-label” and “natural” alternatives was also leading to the search for combinations that would maintain a sufficient “hurdle” against pathogen and spoilage organism growth, thus ensuring food safety and an acceptable product shelf-life.
Christine Endacott-Palmer, microbiology science leader with Unilever Research and Development at Vlaardingen in The Netherlands, described how her company was dealing with the food safety risks in condiments and sauces, posed by these consumer demand changes.
“We use synergistic preservation technologies,” said Endacott-Palmer. Products such as mayonnaise and cooking sauces rely heavily on the fact that they are acidic (typically with a pH below 4.2), contain the preservatives salt, sugar and mustard, and are heat treated to inhibit pathogen growth, she said. Unilever uses sophisticated software models to predict how different process treatments and additive combinations affect product shelf-life.
However, Endacott-Palmer described how changes to manufacturing processes – such as moving from hot to cold processing and reformulation changes – could adversely impact on predicted shelf-life, thus expert knowledge was imperative. To address this problem, Unilever had developed a “tool box” to predict what effect moving to “milder formulations and processes” would have.
She also claimed that as some emerging pathogens became more acid resistant, it would become necessary to have “higher hygiene standards in production”.
But she warned that changes coming into force later this year in the US under the Food Safety Modernization Act could pose problems for companies such as Unilever by restricting the use of computer models to predict the risk and behaviour of products over time.
“It is becoming clear to us that the use of predictive tools [in the US] will become an insufficient method of proof,” said Endacott-Palmer.