A Study on the extraction of coloured and non-coloured fenolic compounds in Boğazkere and Öküzgözü grapes

In this study, the effects of temperature, ethyl alcohol, SO2 and pomace fermentation time on the extraction of coloured and non-coloured phenolic compounds in synthetic medium in Boğazkere and Öküzgözü grape varieties grown in Elazığ Region was studied. For that reason, grapes were crushed and the must was removed. Then, the pomace was macerated in a wine-like synthetic medium at 20 and 30 °C for 14 days. In maceration process, a wine-like synthetic medium containing 0°, 5° or 10° ethyl alcohol with either 0 or 100 mg/1 SO2 addition was used. The pH was adjusted to 3.2 by the addition of 1 N NaOH. According to the results, total phenolic compounds, anthocyanin concentration and colour intensity value increased with an increase in temperature and ethyl alcohol concentration and addition of SO2 resulted in higher levels in samples. Key Words : Boğazkere, Öküzgözü, Extraction of phenolic compounds, Coloured and non-coloured phenolic compounds