3-Isobutyl-2-methoxypyrazine is neutrally perceived by consumers at usual concentrations in French Sauvignon and Fer wines from the Gaillac area

Abstract

3-isobutyl-2-methoxypyrazine (IBMP) is a grape-derived aroma compound responsible for the bell pepper character of wine. It is still unclear whether this molecule is always negatively perceived by consumers. The objective of this study was to establish a consumer rejection threshold (CRT) for IBMP in French white and red wines from the Gaillac area made from Sauvignon and Fer respectively.The best estimate thresholds (BET) were determined by carrying out three-alternative forced choice (3-AFC) tests: 5.5 ng/L for Sauvignon and 16.8 ng/L for Fer. For the estimation of the CRT, consumers (n = 48) received pairs of samples consisting of a base wine and a base wine spiked with an ascending concentration of IBMP. They were asked to indicate which sample they preferred, and the CRT was calculated as the concentration for which the spiked sample was significantly rejected. CRTs were determined at 50 ng/L and 30 ng/L for Sauvignon and Fer respectively.Our findings indicate that IBMP is more acceptable in white wine than in red wine. As IBMP concentrations reported in the literature for Sauvignon and Fer are generally below CRT concentrations, IBMP appears to be neutrally perceived by consumers at usual concentrations in wines from Gaillac made from these two cultivars.Our findings tend to contradict the belief in the wine industry that consumers systematically reject ‘vegetative’ styles of wines, and do not encourage local winegrowers and winemakers to necessarily implement viticultural or enological practices to minimise IBMP concentrations in wine.