Effect of postharvest putrescine and thyme oil application on quality preservation in peach

Peach fruit requires cold storage after harvest due to its soft texture. This study aimed to preserve fruit quality during storage by applying putrescine and thyme oil to peach fruit. Fruits were treated with 2 mM putrescine, 1000 ppm thyme oil, and a combination of putrescine and thyme oil before being stored in cold storage. Peach fruits were stored in perforated plastic containers at 1.5°C and 80% humidity for 10, 20, 30, and 40 days. The study observed that weight loss and decay rates increased during storage. It was determined that the lowest weight loss and decay rates were obtained with putrescine applications across all storage periods. However, the combination of thyme oil and putrescine negatively affected overall pH, titratable acidity, and soluble solids content. In fruits stored for 40 days, the control had the lowest (10.17%) and the combination of putrescine and thyme oil had the highest (12.00%) soluble solids content. At the end of this study, it was concluded that thyme oil causes physical damage to peach fruits during storage due to its excessive acidity, and putrescine is a more effective method in preserving fruit quality.