Effect of UV-C illumination on storage life and postharvest quality of green beans

This study was conducted to find out the effects of different UV-C doses on the green beans stored under modified atmosphere packages (MAP). For that purpose, "Bourgondia" cultivar of green beans were used as plant material. Harvested green beans were treated with 0.1, 0.3, and 0.5 kJ/m2 UV-C doses and stored in MAP at 8 °C for 25 days. Furthermore, the produces were removed at interval of 5 days and kept at 20 °C for 3 days to determine shelf-life performance. The sampling from the cold storage and shelf-life storage was taken on every 5th and 3rd day of storage, respectively. At the end of study, increases in weight loss were found and UV-C illumination had no effects on weight losses. Furthermore, increases in TA and decreases in TSS contents were determined during the storage and UV-C treatments slow down increase trend in TA. During the storage, L* values were increased and C* and h° values were decreased. The total sugar contents were decreased during the storage and UV-C treatments showed a better prevented effect in reduced total sugar. UV-C treatments had no effects on total chlorophyll contents. UV-C illumination application showed effects on total phenolic contents with extension in storage and increased with increase in UV-C illumination dose. Total flavonoid contents exhibited increase initially and later recorded the close value to the initial value. At the same time UV-C illumination and storage duration had no effects on total flavonoid contents during shelf-life conditions. UV-C illumination decreased respiration rate and this decrease were determined to increase with increase in dose. In our study, medium and high doses of UV-C illumination determined damages on 10th day of storage. In our study, it was determined that medium and high doses of UV-C cause radiation damage from the 10th day of storage. No fungal-related deterioration was observed in the storage of green beans under cold storage conditions. However, it was determined higher rate in medium and high doses of UV-C under shelf-life conditions. As a result, 0.1 kJ/m2 UV-C illumination dose in green beans have been found to maintain the quality and it has been determined that it can be used safely for 25 days.