Chemical Composition of Lowbush Blueberry Cultivars

The chemical composition of the lowbush blueberry (Vaccinium angustifolium Aiton) cultivars Blomidon, Cumberland, and Fundy were examined at three stages of fruit maturity, before and after refrigerated storage, in a 2-year study. There were differences (P< 0.001) related to maturity and cultivar in berry fresh weight, percentage dry matter, fruit firmness, percentage soluble solids, titratable acidity, and the concentration of sugar, acids, and anthocyanins. Among the nine organic and phenolic acids measured, seven acids varied among the maturity groups and eight varied among the cultivars. Between the 2 years of study there was a 60% difference in total fruit acid content as well as in the relative amounts of each acid. The 2-year mean profile of lowbush blueberry acids was distinctly different from that recently reported for highbush (Vaccinium corymbosum L.) and rabbiteye blueberries (Vaccinium ashei Reade). The level of certain acids as well as the concentration of anthocyanins increased during cold storage. Estimation of sugar concentration by percentage soluble solids overestimated sugar concentration by 3070. Acid measurement by titration underestimated acid content as measured by HPLC by 61%. Results of this study illustrate the variation in the chemical composition of lowbush blueberry fruit among cultivars, maturities, and seasons, and can be used to compare lowbush blueberries with other Vaccinium species. Lowbush blueberries (Vaccinium angustifolium) are native to Eastern Canada and the Northeast United States, where wild stands are commercially managed and harvested. Lowbush fruit is small compared to highbush (Vaccinium corymbosum) or rabbiteye blueberries (Vaccinium ashei). Since stands of lowbush blueber- ries are made up of numerous wild clones, the commercial lowbush product is more heterogeneous than commercial highbush or rabbiteye blueberries. The mineral and vitamin content of lowbush blueberries was reported by Bushway et al. (1983) and the total N, amino acid, anthocyanin, flavanol, and sugar content was exam- ined by Goueli(1976). Lowbush blueberries contain equal amounts of glucose and fructose but do not contain sucrose (Barker et al., 1963, Goueli, 1976) while highbush blueberries contain fructose, glucose, and small amounts of sucrose (Eck, 1988). Ehlenfeldt et al. (1994) recently reported the organic acid composition of highbush and rabbiteye blueberries and suggest that these two Vaccinium species are distinguishable based on their acid profiles. The purpose of this study was to examine the chemical profile of lowbush blueberry cultivars with emphasis on fruit components that influence sensory quality. The study examines fruit at three stages of maturity, before and after storage, and during two harvest seasons.