Mélange Of Volatiles Distinguish Brandies

Researchers in France trying to tease out the chemical “je ne sais quoi” that distinguishes apple, grape, and plum brandies are reporting that the secret is the relative concentrations of the fruit-based volatile compounds (J. Agric. Food Chem., DOI: 10.1021/jf9045667). A team led by Jérôme Ledauphin of the University of Caen used mass spectrometry to compare the volatiles in Calvados (apple), Mirabelle (plum), Cognac (grape), and Armagnac (grape) brandies. Many of the more than 200 compounds they detected were found in all the fruit brandies. But each type of beverage has its own relative concentrations of these compounds that set it apart. For example, higher concentrations of methyl branched esters such as ethyl 2-methylbutanoate are measured in apple-based Calvados. In plum-based Mirabelle, higher concentrations of aldehydes such as hexanal, heptanal, and nonanal distinguish the brandy and give it what expert tasters call “vegetal and green aromatic notes,” Ledauphin explains. The zest of grape-based brandies comes from so-called whiskey lactones, which give rise to coconut-like odors. Next up in the French group’s research is to figure out when in the fermentation process the distinguishing aromas and tastes develop.