Nutrient solution aeration and growing cycles affect quality and yield of fresh-cut baby leaf red lettuce

© 2015, MTT Agrifood Research Finland. All rights reserved. The objective of this research was to study the effects of nutrient solution aeration (no aeration [NA], low aeration [LA] or high aeration [HA]) and growing cycle (autumn, winter and summer) on the yield, quality, and shelf life of red lettuce as a fresh-cut product grown in a floating system. The specific leaf area, yield and root diameter were affected by the growing cycle. The percentage of dry matter and the nitrate content were affected by growing cycle and aeration, total phenolics and mesophilic microorganism by aeration and storage time, hue angle and chromacity by growing cycle and storage time, and antioxidant capacity, vitamin C, lightness and psychrophilic microorganisms were affected by all three factors. NA conditions increased the antioxidant capacity in summer and vitamin C content in winter. The lowest mesophilic and psychrophilic count was observed in autumn. The effect of aeration on most of the quality parameters measured was influenced by the growing cycle.