Bagging Chopped Lettuce in Selected Permeability Films

Chopped `Salinas' crisphead lettuce (Lactuca sativa L.) was packaged in four types of polymeric films and stored at 1 or 5C for 14 days. Discoloration and off-flavors developed in lettuce stored in the two films in which the naturally produced CO 2 rose above 20%. In the two films (oriented low-density polyethylene) with O 2 transmission rates higher than 3000 ml·m -2 · day -1 ·atm -1 at 22C, CO 2 remained below 20%, O 2 was between ≈ 2% and 15%, and the lettuce was acceptable after 14 days of storage at either 1 or 5C. Appearance and flavor were affected more by temperature than by length of storage.