Effects of ozone and ascorbic acid treatments on quality change of fresh cut leek cv. lincoln during storage

In this thesis, the effects of ozone and ascorbic acid treatments on the quality of leek cv. 'Lincoln' during cold storage were investigated. Harvested leek samples were transferred to the laboratory and divided into 5 groups for treatments. Ozone and ascorbic acid applied leeks were stored at 0 ± 1°C and 90 ± 5% relative humidity for 30 days. Some quality analysis including weight loss (%), pseudo stem firmness (N) total soluble solids (%), titratable acidity (g/100 ml), respiration rate (ml.CO2/kg‐1h‐1), gas composition of package (%), pseudo stem colour, microbial load and sensory evaluation were performed at 6 day intervals during storage. In the study, the pseudo stem firmness in all treatments decreased with increasing storage time. The %2 AA was the most effective treatment in maintaining pseudo stem firmness. The total soluble solid content of control samples was higher compared to AA and ozone treated leeks at the end of cold storage. The amount of TA in leeks decreased at the end of storage compared to the initial values except for %1 AA treatment. The 2 ppm ozone was the best treatment for suppressing respiration rate of leek stems during storage. 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 could be stored for 24 days at 0 ± 1°C and 90 ± 5% relative humidity.The storage quality and life of fresh cut leek can be increased with appropriate dose and duration of ozone. Therefore, further detailed researches are required.