Researches on the phenolic compounds? profile of öküzgözü, bogazkere and kalecik karasi cultivars grown in different regions and their wines

In this research, coloured and colourless phenolic constituents of Öküzgüzü, Boğazkere and Kalecik karası grapes and their wines and the effects of climate conditions on phenolic compounds of these varieties were investigated. High performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) were used for the analysis and identification, respectively of the coloured and colourless phenolic compounds.Fourteen different anthocyanins, including five glucosides, five acetyl-glucosides, and four coumaroyl-glucosides were identified and quantified in Öküzgözü, Boğazkere and Kalecik karası grapes and their wines. In addition to these compounds, two diglucosides anthocyanins (malvidin-3,5-diglucoside and malvidin-3,5-diglucoside- coumaroyl) were detected in Boğazkere grapes and wines. In addition, twenty-six different colourless phenolic constituents including seven flavanols, thirteen phenolc acids, and six flavonols were identified and quantified in grapes and wines. It was determined that the highest level of total anthocyanin was found in Bogazkere grape variety and followed by the amounts in Ökuzgozu and Kalecik karasi varieties. Malvidin-3-glucoside was the major and cyanidin-3-glucoside was the minor anthocyanins in all varieties and total amounts of anthocyanins increased with maturity. With regard to anthocyanin composition Öküzgözü and Boğazkere grapes are similar and higher amount of malvidin-3-glucoside was followed by the amounts of petunidin, delphinidin, peonidin and cyanidin-3-glucosides. In Kalecik karasi grapes, malvidin-3-glucoside was followed by poenidin, petunidin, delphinidin and cyanidin-3-glucosides. Anthocyanin ratio was significantly different among the grape varieties, but no significant was determined between the regions. The amount of total anthocyanin compounds in Boğazkere and Öküzgözü grapes grown in Denizli region was higher than that of these grapes grown in Elazığ region. The concentration of these constituents in Kalecik karası grapes grown in Ankara region was higher than that of Kalecik karası grapes grown in Nevşehir region.The highest concentration of total colourless phenolic compounds was found in Ökuzgozu variety and that variety and was followed by Bogazkere and Kalecik karasi varieties. The amount of colourless phenolic compounds decreased by maturity and significantly varied by grape variety, year and region. Distribution of anthocyanin compounds in Öküzgözü grapes showed similarities with these compounds of Boğazkere grapes. Depending on ripening, proportion of catechin and procyanidin dimer B2 decreased, while proportion of epicatechin increased.