Physiological effects of MAP and calcium chloride treatments on biochemical metabolites and quality stability by reducing respiration rate in sweet cherry fruit during storage

Background: Sweet cherry (Prunus avium L.) is an important fruit species with its high nutritional value and fresh consumption rate. However, it is very sensitive to mechanical damage, decay, water loss and microbial spoilage in the post-harvest period. Therefore, new preservation methods are needed to extend shelf life and preserve quality. In this study, the effects of postharvest 4% calcium chloride (CaCl₂) and modified atmosphere packaging (MAP) treatments on quality traits (weight loss, decay rate, SSC, titratable acidity, pH, respiration rate) and biochemical compounds (organic acids, vitamin C and phenolic compounds) of sweet cherry fruit were investigated. Results: During the storage period, the weight loss reached 7.14%, the lowest loss was observed in the CaCl₂+MAP group. The highest decay rate was measured in the control group with 11.30%, and the CaCl₂+MAP combination was the method that limited decay the most. SSC increased over time, but the lowest levels remained in the CaCl₂+MAP group. The titratable acidity value decreased from 1.12% to 0.82%, CaCl₂+MAP application was the method that best preserved acidity. The pH value increased by 25.2%, the lowest pH was again determined in the CaCl₂+MAP group. The respiration rate decreased by 77%, the lowest respiration rate was determined in the CaCl₂+MAP application. Organic acid and vitamin C contents decreased over time, and the application that best limited these losses was CaCl₂+MAP. Significant decreases were also observed in phenolic compounds, and the combined application preserved phenolic stability at the highest level. Conclusion: CaCl₂ and MAP applications were effective in preserving the quality characteristics and bioactive compounds of sweet cherry fruit, especially the combined application (CaCl₂+MAP) gave the most successful results. Therefore, in order to prevent post-harvest quality losses and extend shelf life, it is recommended that CaCl₂ and MAP applications be evaluated together by the producer and the supply chain.