Physicochemical and nutritional composition, volatile profile and antioxidant activity differences in Spanish jujube fruits

In Spain, jujube can be considered a minor crop; thus, its cultivars have not yet been investigated in depth. The objective of this study was to evaluate the composition, nutritional profile, and volatile composition of three cultivars of Spanish jujube fruits. The total antioxidant activity and phenolic compounds in peel and pulp of the fruits were studied. The obtained results proved that 'Isidro' cultivar presented the largest fruits, had the highest ascorbic acid content, with a good color intensity, total soluble solid content, and glucose and fructose. In addition, fruits of the 'Isidro' cultivar presented together with the 'Phoenix' ones, the highest protein content and juiciness. The cultivar 'Phoenix' behaved differently than the other two cultivars studied; its fruits had significantly lower contents of total phenols, flavonoids and flavonols and these compounds were mainly accumulated in the pulp. In the other two cultivars, bioactive compounds reached higher values and were mainly accumulated in their peels. 'Isidro' was the cultivar that presented maximum amounts of phenols and total flavonoids. Thus, both cultivars 'Isidro' and 'Phoenix' could be promising cultivars to be used in future breeding programs, to obtain fruit with high content of bioactive compounds as well as interesting organoleptic properties.