Phages suppress Listeria and Salmonella growth
Phage technology can suppress the proliferations of pathogens like Listeria and Salmonella during food production processes. Micreos has developed and registered several ‘green’ processing aids based on phage technology. A large American supplier of turkey meat has started treating its poultry products with these all-natural, organic products.
“Phage technology has many interesting applications. It’s used to increase safety in the food industry and as an alternative to antibiotics in pharma,” says Bert de Vegt, managing director of Micreos Food Safety. The company has launched two products that can be used to inhibit Listeria and Salmonella growth on meat, dairy and vegetables. PhageGuard Listex is active against Listeria monocytogenes, whose 20-30% mortality rate makes it a very dangerous food pathogen. PhageGuard Salmonolex is active against Salmonella, one of the best-known food pathogens.
Phages, or bacteriophages, are the most common micro-organisms on the planet. They are everywhere: in the water, food and in and on our bodies. A single gram of cheese for example contains one hundred million phages. Phages need bacteria to reproduce, and in the process they kill the bacteria. This halves the number of bacteria every two days. For each type of bacteria, there is a specific type of phage.
“A phage works like a laser gun,” De Vegt explains. “One type of phage will target one specific bacteria and leave other bacteria and cells alone. That’s the beauty of it. Phage treatment is an all-natural and totally safe alternative to treating meat, poultry, fish and cheese with chemicals like chlorine. Phage treatment does not affect a product’s flavor or aroma and there’s no toxic limit for its application.”
Micreos supplies high concentrations of phages in vials. “In the food industry, the phage solution is diluted before application and then sprayed onto the product, for example. We call this carpet bombing. Using the right dosage is critical in such cases, because you need to make sure every last bacteria gets killed.”
Clean label turkey
Phage treatment has been approved in large parts of the world. The US FDA [Food and Drug Administration] has awarded Micreos’ phages GRAS [Generally Recognized As Safe] status. After extensive testing, a large American turkey supplier started treating its turkey products with phages against Listeria monocytogenes in early 2015. The phage treatment is an all-natural alternative for the company’s previous method of dipping the meat in a chemical bath. Before the turkey is packaged, a special nozzle sprays the phages onto the packaging material, which is then used to vacuum pack the turkey meat, killing any bacteria present.
Treating food products with phages has several benefits. It enables manufacturers to market products with clean labels without the risk of organoleptic or other unwanted changes to the product. The American turkey processing company was the first to introduce large-scale application of phages for food safety purposes, according to De Vegt. “Other companies in Australia, Canada and New Zealand are following suit. And in Norway, the fishing industry, which has problems with Listeria, is looking into treating salmon with phages. Application of our product is definitely cost-effective. Treating meat with lactate costs 5 euro cents per kilo, while treating it with phages costs only 2 euro cents per kilo.”
In the Netherlands, phages have also been approved for use in certified organic products. De Vegt says this will have a big impact. “Psychologically speaking that’s very important. Consumers are asking for products that use natural replacements for disinfectants. I compare phage-treated food products with yoghurt or Yakult. People don’t have a problem with the idea that microorganisms can be beneficial to our health. Therefore, we expect phages to be used more and more in the future.”
Micreos is working on expanding its product range. The company is developing phage applications against E. coli and Campylobacter for the food industry.
Source: Food Valley Society