Role of Postharvest Oxalic Acid Treatment on Quality Properties, Phenolic Compounds, and Organic Acid Contents of Nectarine Fruits during Cold Storage

Due to the soft texture of the nectarine fruit, there are difficulties in long-term storage of this fruit. Therefore, it is of great importance to extend the postharvest storage period of this fruit species. In this study, the effect of postharvest OA (Oxalic acid) applications (0, 0.5, 1 and 1.5 mM) on the quality and biochemical contents of nectarine fruits was investigated. On the 40th day of storage, 1.5 mM OA doses reduced weight loss (1.96%) and fruit flesh firmness (36 N) by approximately 44% and 20%, respectively, compared to the control group. The most effective dose in reducing the respiratory rate was again 1.5 mM OA. The 1 mM OA dose was determined to prevent the decay rate approximately by 16% compared to the control group. Organic acid contents showed a continuous decreasing trend during storage and malic acid was determined to be the dominant acid in nectarine fruits. At the end of storage, it was determined that a 1.5 mM OA dose prevented the decrease in malic acid content approximately 35% more than the control group. Chlorogenic acid and rutin were detected at a higher rate than other phenolics. It was observed that 1.5 mM OA dose prevented the breakdown of chlorogenic acid and rutin compounds more so than other doses during storage. In this study, it was determined that a 1.5 mM OA dose especially protected the quality properties and biochemical contents of nectarine fruits in the cold storage more than the control group.