Comparative study of volatile composition of major Northern Highbush blueberry (Vaccinium corymbosum) varieties

Blueberries originated from North America and the predominant cultivated species are Vaccinium corymbosum (Northern and Southern Highbush), Vaccinium ashei (Southern Rabbiteye), and Vaccinium angustifolium (Low bush). Consumer's demand for high-quality blueberry fruits has driven the interest to better understand the flavor chemistry of blueberry. Forty-five previously identified aroma contributing compounds were further investigated in 11 blueberry varieties, including some developing types. Based on odor activity value, branch chain esters, terpenes, and aldehydes could be the primary aroma contributors to all 11 blueberry varieties. A heatmap with hierarchical clustering dendrogram showed that the three varieties ORUS 235-4, ORUS 235-3, and ORUS-10-1 were close together with a high level of branch-chain esters and, in turn, close to 'Draper' and 'Duke'. However, they differed from the other varieties, including 'Aurora', 'Bluecrop', 'Elliott', 'Legacy', 'Liberty,' and ORUS-202-2. One-way ANOVA analysis demonstrated that terpenoids varied the most among varieties. Also, the Pearson correlation showed terpenoids, except eucalyptol, exhibited a strong positive correlation, especially between linalool and alpha-terpineol. Enantiomer analysis revealed S-(+)-linalool was dominant in all blueberries, whereas the S-(-)-alpha-terpineol was slightly higher than R-(+)-alpha-terpineol. This study provided a detailed volatile composition database for unraveling the complex genetics of the various blueberry flavor aspects to assist the breeding purposes of new blueberry crops.