Effect of package film on the quality of fresh-cut salad savoy

Salad savoy (Brassica oleracea L.) is a vegetable crop that is becoming a valued addition to fresh-cut salad mixes. This study was conducted to develop a modified atmosphere packaging system for fresh-cut salad savoy and to evaluate the effect of film oxygen transmission rate (OTR) on package atmospheres, and consequently product quality changes during storage. Two varieties of salad savoy (white and violet) were cut into approximately 5 cm x 5 cm slices and sanitized in 100 mul l(-1) chlorine solution. The products (85 g each) were packaged in sealed 19 cm x 22 cm polyethylene bags prepared with films of selected OTRs at 8.0, 16.6, 21.4, and 29.5 pmol s(-1) m(-2) Pa-1 and stored at 5degreesC for 25 days. Evaluation parameters included package atmospheres, product respiration rate, color, cut-end discoloration (browning), off-odor, decay, and overall quality. Results indicated that the OTR of the package film significantly (P<0.05) affected package atmospheres, product quality, and shelf-life, under the tested package configuration and storage condition. Packages with 16.6 and 21.4 OTR films attained the desired O-2 (1.4-3.8 kPa) and CO2 levels (3.6-6.3 kPa) on day 10 and throughout the storage period; products stored in these packages maintained freshness with high overall quality scores. Packages with 8.0 OTR film exhibited a rapid depletion of O-2 (to similar to 0 kPa) and accumulation of CO2 (11.0-12.6 kPa), resulting in off-odor, decay and unacceptable quality of the products at the end of storage. Sample, from packages prepared with 29.5 OTR film developed discoloration on the cut-ends due to high O-2 (6.0-7.9 kPa) in the packages. White salad savoy had higher respiration rates and lower quality scores than violet salad savoy. Overall, both white and violet salad savoy maintained good quality and shelf-life throughout the 25-days storage period under the most favorable atmosphere condition.