Effects of pure and mixed cultures of endogenous Saccharomyces and non-Saccharomyces yeasts isolated from narince grapes on white wine aroma

In this study, Narince wines were produced with endogenous pure S. cerevisiae-1088 (Sc-1088), T. delbrueckii-214 (Td-214) and mixed culture (K.k.) isolated from spontaneous fermentations of Narince grapes, and effect of cultures that is used in fermentations on general and aroma compositions of the wines were investigated. Extraction of aroma compounds of the wines were carried out by liquid-liquid extraction method and identification and quantification by GC-MS-FID technique. The sensory evaluations of the wine were determined by the Descriptive Analysis. Total of 49 aroma compounds were identified in Narince wines produce with S. cerevisiae-1088, T. delbrueckii-214 and mixed cultures, their amount were 203 mg/L, 187 mg/L, 229 mg/L, respectively. In pure culture, S. cerevisiae-1088 strain produced higher amounts of esters, volatile acids and lactones while produced lower amounts of volatile phenols and carbonyl compounds than T. delbrueckii-214 strain. The presence of Td-214 yeast slowed down the fermentation and produced lower level of ethanol, higher level of glycerol and volatile acid. According to sensory evaluations, tropical fruit, citrus and honey odours were characteristic of Sc-1088 and mixed culture wines while cooked fruit and apple odours were the characteristic of Td-214 wine. The mixed culture wines was described by heavy body, more acidic and persistence in mouthfeel than compared the other wines. .