Listeria monocytogenes: Prinova to unveil natural preservative that halts bacterial growth
Named PlantGuard AM, the product is said to be an effective growth inhibitor for specific bacteria, yeasts and moulds and can halt the formation of listeria monocytogenes – a hard-to-detect bacteria that produces no taste or smell when present in food but causes the infection listeriosis.
Besides dairy, it can be used in a wide array of applications including fish, meat, fruit, vegetables, cereals and juices. This is because the additive is an amalgamation of preservative compounds of various plants, which combined, are ‘holistically effective against overarching spoilage processes’.
What’s more, it is heat-stable, neutral-tasting, performs comparably against synthetic preservatives, and outperforms other natural alternatives - making it a suitable option for manufacturers looking to achieve clean-label formulations.
“There was extensive research carried out, with support from PhD researchers, to identify the most effective natural preservative compounds,” explained Chloe Downs, technical account manager at Prinova Europe. “These were first isolated individually, but in isolation are only effective for particular spoilage pathways, i.e. spoilage from specific bacteria or oxidation of only specific fats, on their own. These were then combined and tailored to be holistically effective against overarching spoilage processes, for example overall fat rancidity or protection against all gram-positive bacteria.”
‘Significant advance in the preservative space’
A typical issue with natural preservatives is that they are usually not as effective as synthetic options; off-tastes can be another potential worry for formulators.
“There was only a certain degree of functionality you could achieve before factors such as off taints and flavours would start to jeopardise the final product,” Downs added.
“In the case of PlantGuard, the highest potencies of the most effective natural preservative compounds have been harnessed and purified to achieve a product that performs fantastically in application but doesn’t compromise the taste, texture or colour integrity of the products it’s used in. This is a significant advance in the preservative space.”
And since the product doesn’t contain E-numbers, it can be declared on-pack as a natural flavoring, we were told.
Undetectable and multi-purpose
Besides PlantGuard AM, the company offers two other botanical-derived additives under the same range – a rancidity-inhibiting fat soluble antioxidant suitable for use in fat-dominant foods such as pastries, and a water soluble version designed for low-fat applications like breads, spreads and sauces.
All three additives can be combined depending on application – though Downs stressed that to be effective, the range must be added ‘at the earliest stage of processing’.
“The products can all be used at a low-dose rate, and are very mild in flavour and colour, making them undetectable in application and multi-purpose,” she added. “We have found optimal preservative performance by utilising the functionality of all three products, where possible. As food products today are often processed and complex in nature, there is a use for all three in most food systems.”
The low-dose rate and cost-in-use is said to be comparable to alternatives, according to the company.
So, how has the range performed in dairy applications so far? “The range has been shown to be a very effective preservative in dairy products, particularly PlantGuard AM,” Downs said. “This can be used in milk, cheese, yoghurt – depending on the type of spoilage the product is prone to. We have some excellent case studies that show [it] has been particularly effective in a mascarpone cheese application and a crème Brulé dessert, preventing the formation of mould and bacteria at an inclusion of 2,000ppm.”
The PlantGuard portfolio is set to debut in December 2022 at FiE Paris.
