Researches on phenolic substance profiles of some red wines

In this study, dry red wines provided from wineries in different regions of Turkey, produced from different wine grapes (Cabernet Sauvignon, Boğazkere, Öküzgözü, Papazkarası, Shiraz, Merlot, Kalecik Karası, Kuntra (Karasakız) and Karalahna) in 2007 and 2008 years were used.The main goal of this study was determination of phenolic substance profiles of some red wines belonged to our country. Although phenolic substances are low amounts in grape and wines, they have important activities. Phenolic substances are responsible for colour, astringent and bitter taste of red grape and wine. Nowadays, it is important topic that they have health benefits because of their antioxidant properties.To get information about phenolic composition of wines, this study was conducted and total anthocyanin, total tannin and total phenol by spectrophotometric methods were determined. Besides the phenolic composition, physico-chemical analyses of wines such as specific gravity, alcohol, total dry matter, pH, total acidity, volatile acidity, sugar, total and free sulphur dioxide, hue and colour intensities were determined. Sensory analysis (20 score method) was performed to determine sensory properties of some wines that had enough amounts. Results belonged to all analyses were compared according to grape variety, production region and year, and was proved if there is any differences. Also statistical methods were used to show significant differences among the treatments..When the wines were examined in respect to profiles of phenolic subtances; Cabernet Sauvignon I wine in 2008 had the highest amount of anthocyanin (170 mg/L). However, the total anthocyanin in 2007-Cabernet Sauvignon I and 2007-2008-Cabernet Sauvignon II ranged between 64-68 mg/L. Thereby difference between 2008-Cabernet Sauvignon I was statistically significant. The lowest total tannin concentration was determined in 2008-Kalecik Karası (1,30 g/L) and as to the highest total tannin concentration in 2008-Karalahna (5,93 g/L). Total phenol amounts were detected the highest in 2008-Karalahna wine with 4285 mg GAE/L and the lowest in 2008-Kalecik Karası with 1199 mg GAE/L.In sensory analysis, total scores were varied between 11,4 and 14,9 by total 20 score method. Wines produced in year 2007 were ranked as Kuntra (14,9), Kalecik Karası (13,5), Merlot (13,0), Cabernet Sauvignon II (12,5), Cabernet Sauvignon I (12,4), Shiraz (12,0) and Karalahna (11,4) in terms of sensory scores. Wines produced in 2008 were ranked as follow: Merlot (14,4), Kuntra (13,9), Cabernet Sauvignon I (13,1), Kalecik Karası (12,7), Karalahna (12,4), Cabernet Sauvignon II (12,0) and Shiraz (11,4).Consequently, differences between results based on various factors such as grape variety and maturity, practical cultivation techniques, vineyard and vineyard location, climate, properties of soil, region, harvest time, techniques of wine making, storage conditions and time.