Effects of modified atmosphere packaging on quality attributes and physiological responses of fresh-cut crisphead lettuce.

摘要

The present work aimed at evaluating quality attributes and physiological behavior of fresh-cut crisphead lettuce stored under active modified atmospheres and refrigeration. Lettuce heads "Veronica" were commercially harvested in Brasilia, Brazil, and were minimally processed as strips and packed in polypropylene bags with two different active modified atmospheres, and stored at 5 degrees C for 14 days. Every two-day packages were sampled for carbon dioxide (CO₂) and ethylene evolution, oxygen consumption, total chlorophyll content, polyphenoloxidase, and peroxidase activities. It was observed that CO₂ and ethylene evolution increased during the first two days after processing for all treatments as a response to mechanical stresses. Polyphenoloxidase and peroxidase activity presented a slight increase right after processing but showed a tendency to reduce during the experimental period. It was concluded that active modified atmospheres had no significant effects on quality attributes and physiological behavior of fresh-cut lettuce considering the conditions the experiments were carried out.