Strawberry fruit of the cultivars ‘Annapolis’, ‘Cavendish’, ‘Honeoye’, ‘Kent’, and ‘Micmac’ were tagged at the first sign of color development. Ten-fruit samples were harvested at 3 stages of maturity: 50% red, full red, and 24 hours after full red was reached (red+24h). Fruit quality and chemical composition were evaluated immediately after harvest, after 5 days at 1°C (5 days), or after 5 days at 1°C plus 2 days at 15°C (7 days). Three samples were harvested for each cultivar, maturity, and storage treatment combination during the season. Fruit evaluation criteria included firmness, subjective color rating, total anthocyanin content, soluble solids content, titratable acidity, glucose, fructose, sucrose, citrate and malate contents, and headspace volatile composition of intact fruit.

Strawberry fruit ripened rapidly on the plant, going from first blush of color to full red in about 1.5 days. At harvest, fruit firmness was 20% and 35% less in ‘red’ and ‘red+24h’ fruit, respectively, than in ‘50% red’ fruit; however, firmness did not change during storage. After 5 days of coolstorage there was little change in fruit color or anthocyanin content. After 7 days (5 days of coolstorage and 2 days of shelf life), fruit harvested at ‘50% red’ became fully red; and the anthocyanin concentration increased by 140%, 50%, and 30% in fruit harvested at ‘50% red’, ‘red’, and ‘red+24h’, respectively. Soluble solids and glucose content of the fruit did not change during the 2 days of ripening on the plant or the 7 days of storage. Fructose concentrations was 10% lower in ‘red’ fruit compared to ‘50% red’ and ‘red+24h’ fruit. Sucrose concentrations showed an opposite trend, and were 40% or 30% higher in red fruit than in ‘50% red’ or ‘red+24h’ fruit, respectively. During storage, sucrose concentrations decreased by 20% after 5 days coolstorage and 40% after 7 days (5 days coolstorage + 2 days shelf life). Titratable acid content decreased by 3.5% and 8.2% in ‘red’ and ‘red+24h’ fruit, respectively compared to ‘50% red’ fruit. During storage, acidity decreased by less than 3%. Citric acid concentration was 20% and 40% higher in ‘red’ fruit than in ‘50% red’ and ‘red+24h’ fruit, respectively, and increased slightly during storage. Malic acid concentrations decreased by 10% and 20% during ripening and storage, respectively. Esters were the predominant volatiles present in the headspace over the strawberry fruit. During ripening on the plant, methyl esters increased 3 to 5 times while ethyl esters remained unchanged. Volatile esters contributing to aroma increased 50 to 200% during storage.

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