A combination of specific packaging films, cleaning chemicals and modified atmospheres can lengthen the shelf life of fruit and vegetable varieties, according to studies by the USDA.

The use of special films combined with modified atmosphere packaging method and cleaning chemicals has long been known to improve shelf life. However, the study by the USDA’s research service provides smaller processors access to publicly-funded research that can help them compete with the big players in the market.

Fresh-cut fruit and vegetable varieties are still alive, and each respires at its own unique rate. Therefore, a film’s permeability and the amount of oxygen initially infused into a package are key to extending its shelf life. Hundreds of different types of films for packaging fruit and vegtables currently exist on the market. Each type has its own oxygen transmission rate, which allows sliced produce to continue breathing throughout storage and distribution.

If a film’s oxygen transmission rate is too high for the variety it’s wrapping, the product inside will brown. If it’s too low, the product will prematurely decay.

More recent studies have shown that a newer wash treatment eliminated two pathogens–Listeria and Salmonella–on apple slices.

Kenneth Gross, a plant physiologist who heads the PQSL. "We’re conducting research to help find ways to widen the variety of offerings that stay fresh to the last bite."