Postharvest Behavior of butterhead lettuce minimally processed

This experiment was performed to investigate whether increasing calcium concentration in the nutrient solution would increase calcium concentration in the leaves and to improve or extend postharvest shelf life of minimally processed butterhead lettuce. Plants were grown in soilless culture with three calcium concentrations. Every 15 days, plants of each treatment were harvested randomly to determine number of leaves and leaf area. At harvest, ion content and ascorbic acid were measured and finally lettuce heads were harvested. Intact leaves were packed in bags, sealed and stored in chambers at 1 and 8 degrees C for 9 days. Samples were taken every three days to evaluate overall visual quality, oxygen, carbon dioxide, ethylene and weight loss. At the end of the storage ascorbic acid content was determined. Minimally processed butterhead lettuce was not affected by calcium level for whole lettuce grown in nutrient solution.