The natural and clean label trend has the food sector in its grip, as retailers and consumers are keen on products that have ingredients lists short on chemical names and E-numbers. In 2008 market researcher Mintel reported that over a fifth of new products launched that year claimed to contain no additives or chemical preservatives.
For formulators grappling with efficacy and the need to keep costs down, delivering to this mandate can be a tough call. Generally speaking, the desired level of preservation can be achieved more cheaply using chemical preservatives than with natural products.
Dr Tim Landers, project leader at Nizo, set out to investigate possible synergies between different kinds of natural preservatives. Proteins and peptides, ferments and natural compounds like essential oils and herbal extracts all have their own mode of action – as well as their advantages and disadvantages.
He has discovered that lactoferrin, an antimicrobial protein, and thymol, an extract of thyme essential oil, work particularly well together to combat E.coli.
“The combination of both showed an enormous synergistic effect, almost complete inhibition of the growth of this bacterium,” Dr Landers said. “Thus, the synergistic interaction between different classes of natural antimicrobial compounds increases their efficiency, and thereby decreases the costs in use.”
He expects the combination could be put to use in fresh food, meat and animal feed.
The lactoferrin’s action stems from its iron-sequestering capabilities, and the presence of antibacterial peptides making up the N-terminal part of the protein. As for the thymol, its antimicrobial action can be explained by its interaction with biological membranes.
One combination of many
The fruitful combination of lactoferrin and thymol is just one of many potential combinations between different proteins and extracts, and Dr Lambers’ is continuing to study others that could prove helpful to food formulators.
“It is not a one-off, this is a very broad field,” he said.
The research project was initiated by Nizo, rather than being commissioned by a client, as the organisation identified a market need for this kind of knowledge.
Nizo is discussing the findings with its customers, and may consider publishing them in a scientific journal in the future.