Comparison of volatile compositions of 15 different varieties of Chinese jujube (Ziziphus jujuba Mill.)

Jujube (Ziziphus jujuba Mill.) extract has been commonly used as a flavoring ingredient due to its unique aroma. In this study, solid phase micro extraction method was used to extract the volatile compounds in fresh jujube, with the aid of GC-MS for further chemical separation and identification. As a result, 33 volatile compounds, including aldehydes, alcohols, acids, ketones and esters, were identified. Among them, hexanal (276.5-1314 mu g/100g FW), (E)-2-hexanal, (145.1-1876 mu g/100g FW), nonanal (188.2-1047 mu g/100g FW), and n-decanoic acid (58.42-1268 mu g/100g FW) were found to be the major volatile compounds in fresh jujube fruit. Based on the type and amounts of the volatile compounds, 15 Chinese jujube cultivars were divided into 5 clusters through hierarchical cluster analysis and principal component analysis (PCA). Fiver clusters include cluster 1 (LB, HP, LZ, NP, JS, PZ, and YL), cluster 2 (BJ, DB), cluster 3 (PB, BZ, JD and XZ), cluster 4 (JB) and cluster 5 (YZ). According to the PCA, the clusters 1, 2 and 3 could not be discriminated from each other, but clusters 4 and 5 could be separated very well from each other.