Integrated Metabolomic Profiling and Harvest Volatile Signatures Reveal Cultivar-Specific Quality Traits in Blueberries (Vaccinium corymbosum L.)

Blueberries (Vaccinium corymbosum L.) are widely appreciated for their flavor, bioactive compounds, and health promoting properties, yet cultivar-dependent differences in metabolic composition and postharvest stability remain incompletely understood. This study evaluated five commercial blueberry cultivars (‘Aurora’, ‘Chandler’, ‘Elliot’, ‘Legacy’, and ‘Liberty’) at harvest and after 15 days of cold storage (postharvest stage) (4 °C), assessing fruit color, size, firmness, primary metabolites, volatile organic compounds (VOCs), anthocyanins, phenolics, and antioxidant capacity. Cultivar-specific differences were observed in fruit morphology, sugar/acid balance, and biochemical composition: ‘Liberty’ and ‘Elliot’ accumulated higher monosaccharides and disaccharides, whereas ‘Aurora’ and ‘Chandler’ showed higher organic acids and amino acids. Volatile profiling at harvest revealed that ‘Liberty’ exhibited the richest aromatic profile, with elevated aldehydes, ketones, acids, phenols, alcohols, and esters. Postharvest storage caused minor changes in primary metabolites but altered anthocyanin content in a cultivar-dependent manner. Principal component analysis indicated that volatile compounds were the primary factors differentiating cultivars, while primary metabolites largely influenced sweetness–acidity balance. Overall, the results demonstrate that blueberry fruit quality is strongly cultivar-dependent, with cultivar-specific metabolic and volatile signatures shaping sensory and nutritional attributes, and provide valuable information for breeding, postharvest management, and cultivar selection to optimize flavor, bioactive content, and shelf-life.