Study of the content in volatile compounds during the aging of sweet Sherry wines obtained from grapes cv. Muscat and fermented under different conditions

Several experiments of aging in oak wood and stainless steel of sweet Sherry wines obtained from grapes cv. Muscat fermented under different enological conditions have been carried out. These wines were periodically sampled and their volatile content was analyzed using SBSE-GC-MS. A sensory study was also carried out. Data were submitted to different statistical techniques. An important influence of the three factors considered, fermentation type, aging type, and aging time, have been observed. In cluster analysis, the grouping obtained demonstrated that the volatile compounds considered possess sufficient explanatory power to detect the type of aging process and differentiate the two yeast strains studied. In the case of the linear discriminant analysis, high percentages of correct classification were obtained for the three factors considered. Taking into account the global volatile profile, the factor aging type (oak cask or stainless steel) has demonstrated the highest influence on the volatile content of the wines, with those wines from Experiments D4 and D5 (fermented with S. bayanus) and aged in oak wood clearly differentiated from those ones fermented with S. cerevisiae and aged in wood or stainless steel. From a sensorial point of view, the wines fermented with S. Cerevisiae and aged in wood (D1C and D2C) were the most valued ones.