Evaluation of the Storage Characteristics in Maintaining the Overall Quality of Whole and Fresh-Cut Romaine Lettuce during MA Storage

This study aimed to examine the effect of modified atmosphere (MA) storage on the quality and storability of romaine lettuce. Whole and fresh-cut romaine lettuce were packaged with 1300; 10,000; 50,000; 100,000 cc m(-2)& BULL;day(-1)& BULL;atm(-1) O-2 transmission rate (OTR) films and stored at 2 or 8 & DEG;C for 15 days. The respiration and ethylene production rates before pre-cooling were higher in fresh-cut lettuce than in whole romaine lettuce. The reduction in fresh weight for whole and fresh-cut romaine lettuce during storage was less than 0.5%. The CO2 concentration was less than 2%, except for the 1300 cc treatment (at 8 & DEG;C for whole and fresh-cut lettuce) and 10,000 cc (in fresh-cut lettuce). At the end date of storage, the overall quality of the whole lettuce was good, the off-odor was lower in the 10,000 cc treatment, and the 50,000 cc treatment at 8 & DEG;C led to good overall quality in the fresh-cut lettuce. The chlorophyll content of the whole lettuce was maintained at a higher level in the treatment of 10,000 cc at 8 & DEG;C, while it was higher in the 50,000 cc treatments at 2 and 8 & DEG;C in the fresh-cut lettuce. Correlation and PCA confirmed that the main factors affecting the storability and quality of romaine lettuce were fresh weight loss rate, off-odor, and the concentration of CO2. In addition, the storage characteristics of whole and fresh-cut lettuce were opposite to 0 in PC1 and PC2, indicating that the storage characteristics were different depending on the processing type.

Automated summary

This study found that films with different oxygen transmission rates could affect the storage quality and storability of romaine lettuce, with respiration and ethylene production rates, fresh weight loss rate, and CO2 concentration being the main influencing factors. Additionally, the storage characteristics of whole and fresh-cut lettuce were opposite in PC1 and PC2, indicating differences in storage characteristics based on processing type.