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Modified atmosphere packaging and related technologies are increasingly used to extend shelf-life of fresh products. This paper covers the effect of such techniques on increasing shelf life. Salad-cut lettuce was washed in different solutions for a period of 1 min. Then, salad-cut lettuce was packed in modified atmosphere (3–5% CO2, 3–5% O2, 97–95% N2) and stored at 4 °C for 12 days. Quality indicators of packaged lettuce including color, texture, sensory properties, total phenol content and antioxidant activity were analyzed at 1, 3, 6, 9 and 12 days of storage. This study showed that combination of sodium hypochlorite and ascorbic acid was the best treatment to maintain most of the qualitative indicators of lettuce during storage at 4 °C (p < 0.05). Ascorbic acid and cysteine caused synergistic effect in preventing oxidation. Treatments containing calcium lactate and heat shock, caused better crispiness till the 9th day of storage. According to the results of current study, application of MAP alongside implementation of food grade chemicals showed to be remarkably effective in increasing the shelf life of lettuce. [ABSTRACT FROM AUTHOR]

Abstract: Freshly cut lettuce slices (Latuca sativa L.) were fumigated with nitric oxide (NO) gas at concentrations between 5 and 1000μl/l in air at 20°C for 1–4h or dipped in an aqueous solution of the NO-donor compound, 2,2′-(hydroxynitrosohydrazino)-bisethanamine (DETANO) at concentrations between 10 and 1000mg/l for 15s to 60min at 20°C. Development of browning on the cut surfaces was inhibited during subsequent storage at 0°C. The most effective treatments for extending postharvest life of lettuce slices were fumigation with 500μl/l NO for 1h, and dipping in 500mg/l DETANO for 5min. Dipping in DETANO solution was, however, more effective as it generated a 100% increase in postharvest life compared with a 70% increase due to NO gas. Solutions of DETANO in water were found to be relatively stable as the same extension in postharvest life was obtained for five batches of lettuce sequentially dipped in the same solution. [Copyright &y& Elsevier]