Bred in Okayama, Japan, in 1957, Pione grapes are large in size, round to oval in shape, and have a thick, violet-black skin along with a juicy flesh. As a matter of fact, Pione grapes are extremely fragrant and have a very sugary taste with a dominant flavor of grape jelly. Besides, they contain vitamins B, K, and C, copper, magnesium, iron, and potassium. In addition, Resveratrol, one of immune-boosting antioxidants found in grapes, is specifically linked to improving blood sugar regulation by affecting carbohydrate metabolism.