Determination of physicochemical characteristics, organic acid and sugar profiles of Turkish grape juices

Abstract

This study investigated the physicochemical properties, sugar and organic acid profiles of 21 grape juice and 3 sourgrape juice samples in Turkey. The pH, acidity and soluble solids were ranged from 2.64 to 4.19, 3.58 to 30.75 g L-1and 5.45 to 25.45 °Bx, respectively. The turbidities varied between 1.59 and 109.50 NTU and the lowest value wasin the Sultani Çekirdeksiz sour grape juices. The Denizli Karasi sample had the highest color index. The tartaric andmalic acid amounts of the samples ranged from 0.53 to 13.16 g 100-1 g-1 and 0.45 to 30.80 g 100-1 g-1, respectively. Themajor acid was malic acid in the sour grape juice samples and tartaric acid in the grape juice samples. For all samples,glucose and fructose constituted a great part of total sugars. The glucose, fructose and total sugar contents changedfrom 28.45 to 48.00 g 100-1 g-1, 15.88 to 48.75 g 100-1 g-1 and 53.67 to 97.27 g 100-1 g-1, respectively. The highest sugarcontent was observed in Kara Erik and the lowest in Yediveren. As a result; some physiochemical characteristics,sugar and organic acid contents of the examined 24 grape juice samples were revealed by the current work.