Phenolic composition of common produced raisins in Türkiye

Abstract

This study aimed to determine individual phenolic compounds of common produced Turkish raisins. As material, Sultan 7, Antep Karasi and Razaki raisins were used. The HPLC method was performed for the analysis of 11 phenolic compounds. The major phenolic acid was trans-caftaric acid and the major flavan-3-ol was also (+)-catechin. The trans-caftaric acid varied between 21.56 and 46.84 µg/g in the samples and (+)-catechin between 2.21 and 74.12 µg/g. Caffeic acid was the second most abundant phenolic acid with 11.06-21.54 µg/g. The highest gallic acid, (+)-catechin, (-)-epicatechin, caffeic acid and quercetin hydrate concentrations were found in Razaki, and trans-caftaric acid, p-coumaric acid and trans-resveratrol in Antep Karasi. The trans-resveratrol was only detected in Antep Karasi raisin with 0.84 µg/g. The strong significant correlations were observed between investigated phenolic compounds. As result, the phenolic profiles of three Turkish raisins were revealed, and the correlations among these compounds were investigated. The findings on raisins indicated that Turkish raisins are a good source of polyphenols.