Impact of Stabilization Method and Filtration Step on the Ester Profile of “Brandy de Jerez”

Abstract

Brandy stabilization is an important step aimed at decanting the suspended organic and inorganic particles that may cause undesirable turbidity (cloudiness or haze) in brandies, affecting the physico-chemical stability, the organoleptic characteristics, and the consumer’s quality perception of the brandy. This phenomenon originates from insoluble salts, volatile compounds (higher alcohols, fatty acid esters, and others), and ethanol-soluble lignins. Among them, ethyl esters of long-chain fatty acids are considered the main cause of haze formation, due to a decrease in their solubility when brandies are stored at low temperatures. For this reason, producers are recommended to intentionally encourage the formation of haze and then to remove it before releasing the brandy to the market. The purpose of this work was to study the influence of two methods of stabilization, the traditional method at room temperature for 1 year, and cold stabilization for 7 days at −10 °C, on the ester profile of “Brandy de Jerez”. The results were compared with non-stabilized samples, to determine the main changes in the volatile composition. The use of multivariate statistical analyses made it possible to identify the esters (potential markers) most impacted by the stabilization process. It was observed that traditional stabilization yielded the most distinct ester profile, while brandies stabilized at cold temperature displayed a lower impact on their volatile composition. Furthermore, both stabilization processes produced a significant decrease in ethyl esters of long-chain fatty acids, which are the compounds responsible for haze formation.

Keywords

• esters
• brandy
• HS-SPME/GC-MS
• cold stabilization
• multivariate statistics