A comprehensive study on the fruit quality of multiple apple cultivars during harvest and post-harvest

• Harvest timing for 13 cultivars varied widely from September to November. • Softening, sensory quality, and browning differed significantly by cultivar. • Multidimensional value theory identified the optimal edibility time (OET). • Amino acid profiles effectively discriminated between harvest and OET stages. • Chlorogenic acid was a key biochemical indicator of browning susceptibility. Thirteen high-quality apple cultivars with maturation periods spanning from September to November, cultivated in the Loess Plateau region of China, were selected as the focus of this study. A comprehensive investigation was conducted to evaluate changes in quality attributes from pre-harvest to post-harvest storage, along with the underlying physiological and biochemical mechanisms. The optimal harvest period was determined based on the stabilization of key maturity indicators, including firmness, soluble solids content, starch content, and titratable acidity. Storage quality varied considerably among the cultivars. ‘Aztec Fuji’, ‘Ruixianghong’, ‘Scilate’, and ‘Cripps Pink’ exhibited the slowest softening rates and the highest storage potential, with firmness decline negatively correlated with starch and protopectin content. Using a multidimensional value theory, the sensory evaluation results were comprehensively analyzed to determine the optimal edibility time. As ‘Qincui’ should be harvested between 147 and 155 days after flowering and marketed around 120 days after storage at 0 ± 0.5°C to achieve optimal flavor. Soluble sugars, organic acids, and free amino acids contribute to flavor development, with certain cultivars exhibiting similar sensory characteristics as determined by electronic tongue analysis. In addition, ‘Shinano Gold’ and ‘Scilate’ demonstrated low browning susceptibility, making them suitable for processing. ‘Yanfu 10’, although prone to browning, contained high levels of antioxidant polyphenols such as chlorogenic acid. This study offers practical guidance on cultivar selection, harvest, and storage strategies to enhance apple quality and marketability.