Physicochemical Characteristics of Strawberry Fruits as Affected by Cultivar and Fruit Cluster

‘Maehyang’, ‘Seolhyang’, and ‘Keumhyang’, the recently bred Korean domestic cultivars and ‘Tochiotome’, one of major Japanese cultivars were cultivated from September to May in a greenhouse. Ripen fruits in the 1st, 2nd, and 3rd fruit clusters (FCs) were sampled once a month from January 16, 2007 to investigate their physicochemical characteristics. Fresh weights of ‘Seolhyang’ and ‘Keumhyang’ fruits in the 1st and 2nd FCs were higher than those of other cultivars, while that of ‘Tochiotome’ was the greatest in the 3rd FC. Shape of ‘Maehyang’ and ‘Keumhyang’ fruits was conical showing the ratio of length to diameter about 1.5, whereas that of ‘Seolhyang’ and ‘Tochiotome’ was about 1.3. Hue values of ‘Maehyang’ and ‘Keumhyang’ were lower than those of other cultivars in all the FCs. Firmness of all the cultivars decreased as the FC increased and that of ‘Seolhyang’ was lowest in all the FCs. Total carbohydrates content and total organic acids content of all the tested cultivars in all the FCs was not significantly different. Contents of anthocyanin (AC) and ellagic acid (EA) were greatest in ‘Keumhyang’ and ‘Tochiotome’, respectively in all the FCs, and contents of AC and EA increased as the FC increased. Content of ascorbic acid was greatest in ‘Maehyang’ in all the FCs, and that in the 2nd FC was greater than those in the 1st and the 3rd FCs in all the cultivars. Results indicate that the tested cultivars adapted to forced cultivation showed the better physical characteristics of fruits in the earlier FCs, while the contents of antioxidant phytochemicals were greater in the fruits in the later FCs. Results also suggest that the recently bred Korean cultivars are comparative to major Japanese cultivars broadly cultivated in East Asian countries.