Shelf Life of Aquaponically-grown Finstar Lettuce in Different Oxygen Transmission Rate Films

The effects of oxygen transmission rate of packaging material on the shelf life of aquaponically-grown Finstar lettuce was studied. Parameters of packaging headspace gas composition (oxygen and carbon dioxide concentrations), lettuce pH, percentage weight loss, total aerobic microorganisms, and color were analyzed every ten days for sixty days. Finstar lettuce was stored at 4○C in four different types of packages (treatments), including a clamshell package and three film bags with oxygen transmission rates (OTR) of 3.0-6.0 cc/(m2/24 hr/1 atm), 80-90 cc/(m2/24 hr/1 atm), and >225 cc/(m2/24 hr/1 atm). The percentage weight loss of the 3.0-6.0 OTR package (-0.76-1.05%) was lowest while the percentage weight loss of the clamshell package was highest (0.81-7.72%) among packaging treatments. Nearly ½ of the panelists rated lettuce as fresh enough to eat as is after 50 days of storage in 80-90 cc/(m2/24 hr/1 atm) films while lettuce packaged in the other treatments had less that 1/3 of the panelists judging the lettuce fresh enogh to eat as is. The long shelf-life may be attributed to Finstar having resilient genetic properties along with being greenhouse-grown which lessens the possibility of contamination compared to field-grown lettuces.