EFFECT OF TEMPERATURE AND MODIFIED ATMOSPHERE PACKAGING ON STORAGE QUALITY OF FRESH-CUT ROMAINE LETTUCE

The aim of this work was to study the influence of two storage temperatures (0C and 5C) and three packaging films (low density polyethylene of 60 mu m thickness, medium density polyethyle of 60 mu m thickness and polyvinylchloride) on the quality of fresh-cut Romaine lettuce stored under passive modified atmosphere. Results showed that all types of packaging reduced weight loss in fresh-cut lettuces when stored at 0 or 5C. Firmness did not significantly change in response to storage time or packaging type during storage. Ascorbic acid retention was affected by storage temperature and modified atmosphere packaging. The type of polyethylene as packaging material and the final storage time, proved to be the most significant factors as far the visual or color parameter evaluation concerns. The modified atmosphere packaging of fresh-cut "Romaine" lettuce at low storage temperatures (0C) is highly suggested to avoid quality degradation. PRACTICAL APPLICATIONS Results suggest that fresh-cut Romaine lettuce packaged in 60-mu m-thick LDPE and MDPE film bags and stored at 0C exhibited very low quality deterioration as far the estimated firmness, color, ascorbic acid and sensory evaluation concerns. The suitable packaging film and modified atmosphere conditions in conjunction with low storage temperatures can significantly control physiological changes initiated by the processing and storage conditions. According to this, it is possible to reduce browning, sustain the initial ascorbic acid content and finally extend shelf life of the fresh-cut lettuce in a wholesale cold store, during domestic storage or in catering industry.