Volatile components and sensory properties of jujube wine as affected by material preprocessing

Fermented jujube wine, derived from the red jujube berry, has a unique flavor, a mild and sweet taste, and high nutritional value. Among diverse varieties of jujube, Bokjo and the native variety are the most frequently cultivated varieties in Korea. The present study aimed to determine the brewing properties of jujube and to compare the characteristics of fresh and dried fruits of the native and Bokjo varieties for optimal brewing conditions for jujube wine production. We investigated the physicochemical and sensory properties, and we compared the volatile compounds in jujube wine prepared using different methods, through solid-phase microextraction (SPME) GC/MS analysis. The physicochemical properties of jujube wine depended on the drying process rather than the cultivar or the presence of seeds. Sensory properties including aroma and sweetness, which have positive effects on jujube wines, were greater in the whole dried fruit group, while negative properties including grassy aroma, sourness, and bitter taste, were high in the fresh fruit group; these observations contrast their physicochemical properties, as analyzed using dried jujube with seeds. Significant differences were observed in volatile compounds among jujube wine samples. In particular, isoamyl octanoate, isoamyl decanoate, ethyl laurate, ethyl myristate, and 2-phenethyl acetate potentially contribute to the jujube-like flavor of dried jujube wine. These results could be useful as basic data for raw material processing for jujube wine production.