The Change of Microbial Load and Quality in Fresh-Cut Leek Treated with Ozonated Water during Cold Storage

Abstract

In the present research, the effect of ozone treatments on the quality and microbial load of fresh-cut leek cv. ‘Lincoln’ during cold storage were investigated. Harvested leek samples were immediately transferred to the laboratory and divided into 3 groups for treatments. After fresh-cut processes, ozone treated (1 and 2 ppm) and control samples were packaged in polystyrene foam tray covered with stretch film (16 μ) and stored for 30 days at 0 ± 1 ° C and 90 ± 5% relative humidity (RH). Some quality analysis including weight loss (%), pseudo stem firmness (N) and colour (L*,C*and h°), total soluble solids (%), respiration rate (mL CO2 kg‐1h‐1), titratable acidity (g 100 mL-1), microbial load and sensory evaluation were performed at 6 day intervals during storage. Ozone treatments decreased weight loss of fresh-cut leeks compared to control. In the present study, the pseudo stem firmness in all treatments decreased with increasing storage time. The 2 ppm ozone was the best treatment for suppressing respiration rate and maintaining TA of leek during cold storage, although the effect of treatments on TA was not statistically significant. 2 ppm ozone treated leeks had lower yeast, mold and bacteria counts compared to other treatments. As a result, it was determined that fresh-cut leek stems treated with ozonated water (1-2 ppm) could be stored for 30 days at 0 ± 1 ° C and 90 ± 5% RH.