Norovirus is the most common cause of gastroenteritis in both the developed and developing world. Often, fresh produce (such as lettuce or strawberries) becomes a carrier for noroviruses. Produce is susceptible to norovirus contamination before and after its harvested. Usually, food is contaminated by water runoff that contains fecal matter and is then deposited there. When humans handle the food, they become infected with the virus.
The issue with viruses and produce is that viruses can be resistant to cold pasteurization techniques like irradiation. The process of irradiation uses gamma or x-rays to destroy the virus, but it can also change some of the properties of fresh produce in the process.
Now, a researcher from the Institut National de la Recherche Scientifique (INRS), Professor Monique Lacroix, has developed an edible fruit extract spray that makes noroviruses more susceptible to irradiation, meaning that a lower irradiation dose can be used to kill viruses, and in turn, preserves the quality of the produce for consumers.
Lacroix , the lead author of the study published in the February 12th online publication of the Journal of Applied Microbiology, says “Noroviruses usually require an irradiation dose of three kilograys (kGy), but we have shown that the treatment time is reduced by half with this fruit mixture spray, which acts as a natural antimicrobial. Using these natural antimicrobials prevents cell breakdown or brown discoloration.”
Professor Lacroix’s team used a combination of cranberry juice and citrus extract and used it to coat lettuce, which is considered one of the most difficult vegetables to preserve. Lacroix hopes to one day partner with the food industry to test fruit extract treatment sprays on a commercial scale.