Cost-effective produce sanitation for packing houses and wholesalers

With around 25% of produce lost after harvesting due to microbial contamination, and surface pathogens on fruit and vegetables known to cause illness and death, any cost-effective means of reducing surface pathogen loads is welcome.

In the US, Worrell Water Technologies has collaborated with the USDA Agricultural Research Service to develop small pouches that can gradually release chlorine gas. The small, inexpensive pouches can be packed into shipping containers, where they will gradually release chlorine dioxide gas that will reduce pathogen loads on the fruit and vegetable surfaces.

Chlorine is routinely added to wash waters to sanitise produce, and sometimes chlorine dioxide is pumped into storage rooms for the same effect, but this is the first time sanitation can be achieved by packing houses and wholesalers by simply putting a pouch in each shipping container.

One to three pouches are all that are needed per crate or carton and, at just a few cents each, using them shouldn’t add much to the price of the produce.

The pouches feature a semipermeable membrane so the gas is vented at a slower rate, avoiding problems of chemical burn that could occur if the gas is released too quickly.

Laboratory tests showed a 100,000-fold reduction in E. coli levels in inoculated grape tomatoes stored with the pouches and further studies are underway to assess the pouch’s effectiveness on other specific fruits and vegetables.

The study results have been published in HortScience.