Spectrophotometric determination of ascorbic acid in grapes with the Prussian Blue reaction

The objective of the present work was to adapt the Prussian Blue reaction for the determination of ascorbic acid. The procedure was successfully applied for the determination of ascorbic acid in red and white grapes (Vitis vinifera L.) just previous ingathering. In the present work was used the red and white grapes from Murfatlar vineyard: Mamaia, Cabernet Sauvignon, Merlot, Pinot Noir, Chardonnay, Sauvignon, Muscat Ottonel and Riesling Italian. The results were situated in the range of 0.67 - 1.79 mg vitamin C/100g product for red grapes and respectively 0.50 - 1.49 mg vitamin C/100g for white grapes.