Physicochemical Properties and Antioxidants Capacity of Baby Leaf Lettuce Influence by Modified Atmosphere Packaging

Freshly harvested baby leaf lettuce (Lactuca sativa L. cv. ‘Red romaine’) leaves were packaged with 1,300, 20,000, 40,000, or 100,000 cc/m2 day atm oxygen transmission rate (OTR) packaging films as modified atmosphere packaging (MAP), as well as perforated film to store at 8 ℃ with 90% relative humidity in order to determine the suitable OTR film on the basis of physicochemical properties and antioxidant capacity. The results indicated that at 8 ℃, the 20,000 cc OTR film modified the atmosphere created in the package so that it consisted of 19.95 - 19.25% oxygen, 1.55 - 4.90% carbon dioxide, and 8.06 - 5.10 µL/L ethylene. Changes in quality including weight loss, visual quality, chlorophyll, color (L*, a*, b*, chroma, and hue angle ºh), and off-odor were the smallest in the 20,000 cc OTR film. The 20,000 cc OTR film also exhibited the highest shelf life at 30 days. The anthocyanin content was higher and the peroxidase, which indicates browning, was lower in the 20,000 cc OTR film compared to the other treatments. In the baby leaf lettuce, the antioxidant capacity was tested and determined with flavonoid, phenolic content, DPPH (1,1-diphenyl-2-picrylhydrazyl) and total vitamin C, which all showed increased levels in the 20,000 cc OTR film. Therefore, the 20,000 cc OTR film as a MAP could be useful for the cold chain distribution of baby leaf lettuce for the purposes of maintaining the physicochemical properties and antioxidant capacity and earning foreign currency by satisfying consumers.