The Effect of Barrique Oak Barrel on the Esters Concentration during Ageing of Cabernet Sauvignon Grape Brandy

Grape brandies are one of the most popular alcoholic beverages in the world, and the most popular are Cognac and Armagnac. Besides these two brandies, which are subject to stricter regulations, grape brandy is produced all over the world, Spanish brandy from the Jeres region, South American brandy Pisco from Peru and Chile, German brandy called Weinbrand and so on.. According to the European Union legislation, brandy is a spirit drink (alcoholic beverage) produced from wine spirit and aged for at least six months in oak casks smaller than 1000 litres in capacity or twelve months with oak receptacles. Esters represents one of the most important group of volatile compounds influencing brandy aroma. During ageing, the content of esters increases as a consequence of the slow esterification of different organic acids with ethanol. The predominant esters in Cognac and Armagnac are isoamyl acetate, hexyl acetate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, and ethyl laurate. Accordingly, the aim of this study was to investigate the effect of 3 L barrique oak barrel on the predominant esters during six months of ageing of Cabernet Sauvignon grape brandy. The esters were analysed by gas chromatography with a mass spectrometer (GC/MS). The highest concentration of investigated predominant esters during ageing is determined for ethyl octanoate (95.41 - 135.67 mg/L), followed by ethyl decanoate (51.61 - 106.86 mg/L) and ethyl hexanoate (38.99 - 104.39 mg/L). Together these three esters accounted for 78.36 - 82.55 % of investigated esters.