Ripening temperature shapes the flavor metabolite composition in blueberry fruit

• Titan's sugar-to-acid ratio at a higher temperature may suit better warmer climate • Titan's Glu-to-Fru ratio at a higher temperature may inflict a sweeter taste • Higher temperature affected VOCs in Biloxi, while the harvest-date on Titan • Higher temperatures reduced levels of key aldehydes, esters, and terpenes volatiles High ripening temperatures alter blueberry fruit chemistry, yet the underlying metabolite shifts remain poorly defined. In this study, two blueberry cultivars, southern highbush ( Vaccinium corymbosum cv. Biloxi) and rabbiteye ( Vaccinium virgatum cv. Titan™), were grown under two controlled day/night temperature regimes, 20.0/16.0°C and 30.0/24.0°C, for two consecutive seasons. The negative impact of higher temperatures on fruit weight, with reductions of up to 34%, and the sugar-to-acid ratio was more significant in Biloxi than in Titan, highlighting Titan’s relative advantage in maintaining fruit quality and taste under heat stress. Higher temperatures also impacted total volatile organic compounds in Biloxi, but not in Titan. Still, changes in key volatile organic compounds, including geraniol, linalool, and methyl 2-methylbutanoate, were detected in both cultivars that could impact the berry flavor. Our results demonstrate how temperature affects blueberry physiology and flavor traits and the adaptability of specific cultivars, i.e., Titan, to higher temperatures. The finding stresses the importance of adapting and optimizing genetic traits to environmental factors under climate change.