Perhaps, phage in food is both an innovation and a contamination. Bacteriophages are the most abundant organisms in the biosphere. If you took all the phage particles on earth and lined them up, end to end, they would cover a distance of two light years, approximately half way to Alpha Centauri. There are a lot of them, and they’re very small. In fact, you probably eat them everyday without even knowing it! But what is their function? And, how can bacteriophages be innovative?
What Is a Bacteriophage?
Phages are viruses that infect bacteria. Essentially, they are to bacterial pathogens, what ‘bad’ bacteria are to us. They were first discovered in 1915, and researched for their antimicrobial properties. However, they were largely overshadowed in the West by antibiotics, and were disregarded for a long time in antimicrobial research. Meanwhile in Georgia (former USSR), research continued and bacteriophages were developed into functional therapeutics for many diseases. More recently, the West has researched bacteriophage for new antimicrobial technologies. So what does this have to do with food?
Current Food Preservation Methods
The latest estimates show $77.7 billion annually in healthcare spending as a result of food-borne illnesses. Before shelf-life labels, spice or sugar or salt, ice, as well as other methods preserved food.While food preservation has advanced, like bacteriophages, there is still room for innovation.
Common antimicrobials used in food products include; acids, such as lactic, acetic or citric acid; chemicals, such as trisodium phosphate, chlorine dioxide or sodium nitrate; and biological agents, such as lysozyme, lactoferrin and nisin. These molecules work by inhibiting bacterial growth, either through modulation of the chemical environment or through direct biological action against the bacteria. For chemical agents, the problem comes from a growing concern among consumers about the toxicity of the chemicals. While the evidence for toxic effects is not well established, would you feed your family something if you weren’t sure? The biological agents generally have a better consumer perception as they can be viewed as ‘natural’. But, they tend to be less potent, and the potential of bacteria to develop resistance to such agents is a very real concern.
Why Phages Are the More ‘Natural’ Option
Bacteriophages present a number of advantages over existing antimicrobials. They are highly targeted; in the same way that you wouldn’t worry about infecting your dog with your cold virus. Bacteriophage infections can be very specific about what bacteria they infect, and, in some cases, specificity goes down to the strain level. This targeted mechanism also means that they do not present a threat to humans, or the ‘good’ bacteria we rely on. This means that if phages are used in a ‘live’ product, such as yogurt, they will not affect the quality or taste by indiscriminately wiping out all the bacteria. This is frequently a problem with chemical additives.
As with the majority of new biotechnologies, regulation is a key barrier to commercialization. In the case of a phage, there is uncertainty around whether it should be classified as an additive or as a processing aid. This depends on whether the phage can prevent recontamination of food, or if they provide only a single sterilization. If they are active as antimicrobials throughout the shelf-life of a food, the phage would be classified as an additive. Whereas, if they are bactericidal for only a short period of time after being introduced to the food, they would be classified as a processing aid. This is an important differentiation.
The Commercialization of Phage Products
A key milestone came in August 2006 when the FDA approved their first bacteriophage preparation for direct addition to human food. Since 2006, the FDA has approved several preparations, including ListShield™, EcoShield™, and SalmoFresh™ by Intralytix, and Listex™ P100 by Micreos. Canada, Australia and New Zealand have since followed suit and approved specific bacteriophage products. There are no phage products that have been widely approved in Europe, however, Denmark and Switzerland have authorized the use of specific phage products, independently of the European Food Safety Authority (EFSA). In the U.S., phage products are widely approved as processing aids, whereas, in Sweden and Denmark, they are approved as additives.
After a long hiatus during the antibiotic era, bacteriophage research is gaining momentum again in the West. Over the past 10 years, a number of phage-containing products have been commercialized, and several legislative hurdles have been passed. Outside of food preservation, there is also garnering interest from the pharmaceutical, cosmetic and agricultural industries.
Although challenges, such as consumer perception and long-term safety and efficacy trials remain, the partnership between humans and bacteriophages looks to be a fruitful one.
