Brettanomyces metabolites using temporal check-all-that-apply
Brettanomyces spoilage in wine is due to the production of metabolites, which together create a distinctive ‘Bretty’ aroma and flavor profile. The objective of this study was to assess the influence three wine flavor matrices have on consumer perception and acceptance of wines containing high and low concentrations of Brettanomyces-metabolites. A commercial Shiraz wine was altered through additions of whiskey lactone (oaky) and 2-isobutyl-3-methoxypyrazine (green). The unaltered Shiraz wine, along with oak and green compositions were spiked with either low or high concentrations of 4-ethylphenol (4-EP), 4-ethylguaiacol (4-EG), and isovaleric acid (IA). All wines were evaluated by consumers (n=105) using check-all-that-apply (CATA) and temporal check-all-that-apply (TCATA) for wine aroma and flavor, respectively.
Wine flavor was additionally evaluated using a ranking evaluation where the top three most prominent attributes were reported. Lastly, consumers evaluated each sample on overall liking. Consumers were classified as having low, medium, or high wine knowledge level, in addition to wine industry experience. Consumers described differences in flavor and aroma attributes across all samples. Oak wine treatments more strongly masked the perception of Brettanomyces-metabolite associated aroma attributes in comparison to green wine treatments. As concentrations of 4-EP, 4-EG, and IA increased from the low to high Brett levels Brettanomyces¬-metabolite associated flavor terms commonly increased in citations by consumers (p<0.05). At the high Brett treatments, citations of Band-Aid, smoky, and leather flavor attributes were all significantly lower when oak was present. Mean liking across all wine samples significantly decreased for consumers in the medium or high knowledge levels as well as for consumers who indicated having wine experience (p<0.05). Results demonstrated the influence of wine composition, and consumer wine knowledge on the perception of Brettanomyces-metabolites and provided valuable information to the wine industry as to how composition may influence the perception of wine spoilage.
Schumaker, M., Diako, C., Castura, J.C., Edwards, C.G., & Ross, C.F. (2018). Influence of wine composition on consumer perception and acceptance of Brettanomyces metabolites using temporal check-all-that-apply methodology. Society of Sensory Professionals 2018 Conference. 26-28 September. Cleveland, OH, USA. (Poster).