A research to solve the problem of quality losses occuring in cold storages of Kabaaşı and Hasanbey apricot varieties for table consumption

This study was carried out in 2021 and 2022 to determine the enzymatic and biochemical changes and to reveal their relationship with fruit browning and quality losses occurring in the fruits of in stored in normal atmosphere (NA) and modified atmosphere packaging (MAP) environments, which fruits were harvested at two different altitudes (1000-1600 m) and maturity (early-mature) in Hasanbey and Kabaaşı cultivars. Fresh apricot fruits were stored at +4 and +1 oC under %90-95relative humidity conditions for eight weeks. Pomological, microbiological analyses, sorbitol content, total phenolics content (TPC), polyphenol oxidase (PPO) enzyme activity, O2, CO2 level, respiration rate and ethylene amount were determined in fruit samples at 15-day intervals. During cold storage, fruit firmness (FF) and total acidity (TA) decreased, and the amount of soluble solids content (SSC) and pH increased. It was determined that MAP +1 oC conditions were more suitable than other applications for storing fresh apricot fruits without loss of quality. Fruit browning occurred during cold storage in the Kabaaşı cultivar fresh fruits collected in the early harvest period from trees at an altitude of 1600 m. However, no browning occurred in fruits collected at the mature stage at the same altitude. It were analyzed TPC as 963.17 mg gallic acid equivalent/kg fresh weight (mg GAE/kg FW) and PPO as 2089.93 unit/mg protein (U/mg prot) in the early harvested Kabaaşı cultivar fruits at an altitude of 1600 m and where browning occurred. On the other hand, in Kabaaşı fruits (1600 m altitude mature stage) where fruit browning did not occur, TPC was analyzed as 502.09 (mg GAE/kg FW) and PPO was analyzed as 1779.06 (U/mg prot). No browning occurred in Hasanbey apricot cultivar fruits TPC 435.81 (mg GAE/kg FW) and PPO 1051.27 (U/mg prot). It is foresighted that the browning of Kabaasi fruits during storage and transportation may be related to the high TPC and high PPO enzyme activity. It is recommended to take into account the browning of the fruit in the new orchard establishment with the Kabaaşı cultivar and harvesting fruits in the mature stage in high altitudes trees. KEYWORDS: Apricot, Preservation, Fruit Blackening, Polyphenol Oxidase, Kabaaşı