INFLUENCE OF DIFFERENT OAK CHIPS ON AROMA COMPOUNDS IN WINE

Abstract

Oak wood has considerable influence on amount of aroma compounds in wine. During the time, when wine is in contact with oak wood, compounds typical for wood diffuse into wine and enrich its aromatic complexity.
Concentration of diffused aroma compounds in wine depends on several factors as contact time, storage conditions, wine properties, geographical origin and toasting degree of oak wood. Because of very small quantities of volatile aroma compounds in wine, it is necessary to use sensitive method as gas chromatography with appropriate sample preparation, to concentrate and analyse the relevant volatiles. In our work, four different wines and eight chips samples with different geographic origin and degree of toasting were used. With GC-MS following substances were determined in wines after 30 days of maceration with oak chips: furfural, 5-methylfurfural, guaiacol, 4-ethylguaiacol, eugenol, isoeugenol, cis- and trans-whiskey lactones, 4-ethylphenol.
Our results show, that the degree of toasting influences the concentration of furfural, guaiacol and cis- and trans- whiskeylactone. Higher toasting leads to an increase of furfural and guaiacol and a decrease of cis- and trans-whiskeylactone in wine. The highest increase of volatile aroma compounds was determined in wine samples with French oak chips with intense toasting. We did not find any specific, definite differences among chips with different geographic origin.