Need for sulphite alternatives is ‘phenomenal’

Campden BRI has had a “phenomenal number of enquiries” from food manufacturers about its project to explore alternatives to sulphites, reflecting how significant a challenge this issue represents in the trade, according to the scientist leading the study.

However, it is still keen to work with more manufacturers and is urging firms that have not already done so to complete an online survey​ detailing which sulphites they use, what function they perform, plus how, and at what stage in the manufacturing process they are used.

Campden BRI is one of nine partners in the three-year EU-funded project SO2SAY​, which is exploring a variety of approaches to replacing sulphur dioxide, said project leader Craig Leadley. “We’re only a few months in, but we’ve had a phenomenal level of enquiries already. At the moment we are collating responses to the survey, but would still welcome further enquiries from industry on this project.”
Sulphur dioxide and its releasing salts are widely used in food and drink production, thanks to their antioxidant properties and ability to inhibit polyphenol oxidase, an enzyme that makes food go brown, said Leadley.
However, the food industry has been exploring alternatives for some time, primarily because sulphites do not sit well with ‘clean-labelling’ initiatives, but increasingly because manufacturers do not want to handle allergens on site, he added. Sulphites also reduce vitamin B1 uptake from food.
Campden is also keen to discover the extent to which manufacturers have already explored alternatives and how efficacious - and cost-effective - these have proven, said Leadley. “What is most likely is that every product or process will need a distinct solution.”

There are three strands to SO2SAY: the development of plant extracts with similar antioxidant and antimicrobial qualities to sulphites; enzyme inactivation to prevent browning; and novel processing and packaging technologies. Campden will be addressing the last two, said Leadley.

In some cases, the solution is fairly straightforward. By vacuum packing diced potatoes, for example, Northern Foods no longer dips them in water containing sulphites to stop them going brown - enabling it to clean up labels on ready meals.

In other cases, said Leadley, novel technologies would be required. “We are particularly interested in more gentle techniques to inactivate polyphenol oxidase but we’re also looking at novel gas mixtures for use during processing and packaging.”