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The effect of malolactic fermentation (MLF) on the volatile composition of white wines made from autochtonous grape variety Kraljevina was studied by inoculation with selected lactic acid bacteria. At the end of malolactic fermentation, after the decomposition of the malic acid present in wine the non volatile compounds were analyzed by HPLC, while volatile compounds were analyzed by gas chromatography. All wines were also sensory analyzed. Results showed changes in acetaldehyde, some higher alcohols, ethyl esters, free and bound monoterpenes and some organic acids that contribute to enhance the sensory properties and quality of Kraljevina wines that underwent malolactic fermentation., Istraživan je utjecaj malolaktične fermentacije (MLF) na sastav hlapivih spojeva u vinima Kraljevine primjenom selekcioniranih mliječno kiselih bakterija. Malolaktična fermentacija te analiza nehlapivih spojeva provedena je na HPLC-u dok su hlapive komponente analizirane pomoću plinske kromatografi je. Sva vina također su i senzorno ocijenjena. Rezultati su pokazali promjene u koncentracijama acetaldehida, nekih viših alkohola, etil estera, slobodnih i vezanih monoterpena te pojedinih organskih kiselina što je pridonijelo poboljšanju senzornih svojstava i kvalitete vina Kraljevina u kojima je provedena malolaktična fermentacija.

Changes in some aroma compounds and sensory properties caused by different commercial S. cerevisiae strains and by epiphyte microorganisms in Chardonnay wines were investigated. Wines fermented with the Lalvin-71 B strain contained significantly lower concentrations of alcohol, isoamyl alcohol, isobutanol and total acidity than the wines obtained from spontaneous and other inoculated fermentations. The highest concentrations of 2-phenyl ethanol and 2-phenyl ethyl acetate were found in the spontaneously fermented wines, whereas no essential changes in these compounds were found among the wines of other treatments. Compared to the spontaneous fermentation, Lalvin-71 B strain fermented wines had somewhat higher concentrations of butyric and caproic acid and ethyl butyrate. Lalvin-71 B strain fermented wines were assessed as the best whereas the quality of the wines produced with Lalvin aromatic-2056 strain was the most inferior in quality.

Traminer wines produced by usual tehnology for white wines and by maceration for 3 hours with and without pectolytic enzyme addition were investigated for the differences in chemical composition and sensory properties.Chemical analyses and sensory testing were performed immediately after fermentation and twelve months after bottle aging.The analyses of higher alcohols and esters were done by gas chromatography.The paired sample test and ranking method were used for sensory evaluation.The wines made from grapes macerated with pectolytic enzymes contained the highest concentration of ethyl acetate, acetates of higher alcohols and fatty acids ethyl esters.At the same time the lowest total higher alcohol concentration with exception of 1-propanol was established in the above metioned wines.There was no difference in the concentration of ethyl lactate and diethyl succinate among the wines of all treatments.After one year period of bottle aging no changes were noticed in the concentration of higher alcohols.The decrease of the acetates of higher alcohols, ethyl esters of fatty acids were noticed in all observed wines while the concentration of ethyl lactate and diethyl succinate significantly increased.The best evaluated were the wines produced from pectolytic enzymes macerated grapes, while the others were of inferior quality.