Evolution of Markers Involved in the Fresh Mushroom Off-Flavor in Wine During Alcoholic Fermentation.

The fresh mushroom off-flavor (FMOff) is due to several C8 compounds such as 1-octen-3-one, 1-octen-3-ol and 1-hydroxyoctan-3-one, among others. Recently, glycosidic precursors of some FMOff compounds have been identified in grape musts, but the evolution of such compounds during alcoholic fermentation (AF) remains poorly studied. Therefore, the aim of this work was to monitor both FMOff glycosidic precursors and volatile compounds during AF by comparing healthy and -contaminated musts.

First identification of a new molecule involved in the fresh mushroom off-flavor in wines: 1-hydroxyoctan-3-one.

The fresh mushrooms off-flavor (FMOff) has been appearing in wines since the 2000 s; the C8 compounds, 1-octen-3-one, 1-octen-3-ol and 3-octanol are involved in this specific taint, yet they alone do not fully explain its occurrence. The objective of this work was to identify by GC-MS new FMOff markers in contaminated matrices, to correlate compound levels with wine sensory characterization and to determine the sensory attributes of 1-hydroxyoctan-3-one, a new candidate involved in FMOff. In practice, grape musts were artificially contaminated with Crustomyces subabruptus, and fermented to obtain tainted wines.

Identification of a Glycosylated Fraction Involved in Mushroom Off-Flavors in Grapes: Influence of Gray Rot, Powdery Mildew and .

An organoleptic defect, termed fresh mushroom off-flavor and mainly caused by the C8 compounds 1-octen-3-one, 3-octanol and 1-octen-3-ol, has been identified in wines and spirits since the 2000s. The aim of this work was to identify the presence of glycosidic precursors of these C8 compounds and to evaluate the influence of different molds on the glycosylated fractions of three grape varieties. Must samples contaminated by molds (gray rot, powdery mildew and ) and three levels of attack severity (from healthy to 10-15%) were studied.