The distinctive flavour of New Zealand Sauvignon blanc: Sensory characterisation by wine professionals

The distinctive New Zealand wine style “Marlborough Sauvignon blanc” was investigated by sensory characterisation, by judgments of typicality, and by chemical analysis of selected aroma compounds. Typicality was defined in terms of perceived representativeness where good examples of the concept were considered more typical. Wine professionals undertook three sorting tasks and a descriptive rating task involving 15 Sauvignon blanc wines from New Zealand and France. Ortho-nasal and global (retronasal and taste) data were each considered. Wines were sorted into experimenter-provided categories of “green” or “not green”, “ripe” or “not ripe”, and “good varietal definition” or “not good varietal definition”. To elucidate the critical components of representativeness, typicality ratings for each wine were considered in relation to descriptive ratings of specific flavours, to the sensory data from the three sorting tasks, and in relation to the concentrations of two aroma compounds, namely 3-isobutyl-2-methoxypyrazine (IBMP) and 3-isopropyl-2-methoxypyrazine (IPMP). Results demonstrated that wines considered to have good varietal definition were also rated higher on typicality with respect to Marlborough Sauvignon blanc than wines that were judged to be lower in varietal characteristics. The data also showed that the higher-order flavour concepts of Green and Ripe were mutually exclusive but each was essential to the concept of a typical Marlborough Sauvignon blanc. Specific flavour characteristics (e.g., green capsicum; boxwood) were predictive of high typicality ratings for a wine, whilst others (e.g., mineral) were predictive of low typicality ratings. The chemical concentrations of IBMP and IPMP correlated positively with perceived green flavours, and inversely with perceived ripe and fruity flavours. The data are interpreted within a cognitive model of conceptual structure [Rosch, E., & Mervis, C. (1975). Family resemblances: Studies in the internal structure of categories. Cognitive Psychology, 7, 573–605] that considers not only the ideal or prototypical Marlborough Sauvignon blanc but also the limits to the variability in flavour profile that can be tolerated by experienced wine professionals for a wine to be perceived as typical of its style.