Influence of pH and Sulfur Dioxide in Unaged Wine Distillates on the Physicochemical and Sensory Profile of the Brandies de Jerez

Abstract

Brandies are spirits produced from wine spirits and wine distillates aged in less than 1000 L oak casks for at least 6 months. The composition of each brandy is determined by its raw material and its aging. During aging, two different phenomena occur: the extraction of compounds from the cask wood and reactions between the different compounds. Characteristics of the casks have a significant impact during this process. Those casks that have previously contained some type of Sherry wine give rise to the so-called Sherry Cask®, which not only contributes to the compounds from the wood but also to those that were originally found in the Sherry wine previously aged in them. The quality of brandy is also determined by the physicochemical composition and characteristics of the distillate, which depends both on the quality of the distilled wine and on the distillation process itself. This work studied the effect of sulfur dioxide and the role that the pH of the distillate plays on the physicochemical and sensory composition of three brandies aged 24 months in a static system of Sherry Casks®. The analyses were carried out following the OIV methods. Results have revealed that high levels of sulfur dioxide and the distillate pH significantly condition the extraction of phenolic compounds and organic acids from the wood, as well as reactions such as hydrolysis or esterification that take place between the compounds in the spirits. These factors have led to a differentiated sensory evaluation of the final brandies.