Water-soluble vitamin content of sun-dried Corinthian raisins (Vitis vinifera L., var. Apyrena).

BACKGROUND: Corinthian raisins are dried vine products, representing approximately 3% of the world dried vine fruit production. The majority of Corinthian raisin production is of Greek origin. Studies on the B-group vitamin content of Corinthian raisins produced in Greece as well as on the effect of region and cultivation altitude on the B-group vitamin content are absent in the literature. RESULTS: Corinthian raisin vitamin content was evaluated by reversed-phase high-performance liquid chromatography after acid and enzymatic hydrolysis in terms of raisin subcategory, i.e. regions of cultivation, crop-to-crop variations, and cultivation altitude. Eight vitamers from five different vitamins were identified and quantified in Corinthian raisins. Vitamin B3 (0.77-2.82 g × 10-2 × kg-1 ) was found to predominate, followed by B6 (0.27-0.37 g × 10-2 × kg-1 ), B1 (0.19-0.22 g × 10-2 × kg-1 ), and B2 (0.10-0.15 g × 10-2 × kg-1 ). B9 content was up to 7.1 g × 10-5 × kg-1 . Minor differences were observed among regions of cultivation, cultivation altitude and crop-to-crop variations. CONCLUSION: This study revealed the presence of several water-soluble vitamins in Corinthian raisins that, together with other health-promoting micronutrients present in the product, further reinforce its place as part of a healthy diet. © 2019 Society of Chemical Industry.