Perceived minerality in sauvignon blanc wine: Chemical reality or cultural construct?

Wine Minerality and Funkiness: Blending the Two Tales of the Same Story

In wines, minerality is a complex concept with increasing popularity in scientific research and the wine press. The flavour conceptual space of mineral wines comprises sulphur-reduced aromas, such as flint, wet stone or chalk associated with freshness and lingering mouth perceptions. Professionals do not consider the perception of sulphur-reduced flavours as an off-flavour. Indeed, this sort of reduction is a cue for the recognition of minerality under a likely top-down mental process. However, untrained consumers perceive these aromas as unpleasant. This different qualitative assessment hampers the communication between professionals and amateurs. This review aimed to describe the perceptions of minerality by experts and novices to promote their mutual understanding. Funkiness is proposed as a descriptor of mineral wines when tasted by unexperienced consumers. The chemical basis of minerality and winemaking options were explored to understand their implications on sensory perception. Mineral flavours have two main features. The first comprises ephemeral aromas that may be described as funky, given their association with sulphur-reduced molecules. The second is linked to the fresh and vivacious lingering mouthfeel perceptions that remain after the reductive aromas vanish. Consumers recognise this dual perception by demonstrating positive emotional responses of surprise during tasting. Then, the perception of minerality is a question of cognition and not of particularly developed sensory skills. Appropriate tasting approaches encompassing emotional responses and emergent properties (e.g., harmony, depth, persistence, complexity) appear essential to understand the nature of wine minerality and to determine when it may be regarded as a surrogate for fine wine quality.

The Influence of the Bottle’s Price and Label Reported Information on the Perception of the Minerality Attribute in White Wines

The use of the descriptor “minerality” in a wine has increased in the last few years. This term is frequently used to describe wines closely associated with their terroir. This concept represents the complete natural environment in which a particular wine is produced, including factors such as the soil, topography and climate. In addition, the term “minerality” is frequently used to increase the price of the bottle. However, little is known regarding how this complex concept is perceived by consumers and whether they use this extrinsic information related to the term “minerality” in the purchasing process. The aim of this study is to understand how the term “minerality” could influence consumers when they purchase wine when this descriptor is included as an extrinsic characteristic on the label and in the price of the bottle. For this purpose, the so-called CATA (check-all-that-apply) methodology was used with a panel of 25 judges in order to define the attributes that a “mineral” wine should contain in order to be chosen and if the information displayed on the label and the price could influence consumers in that process. This technique is a dynamic sensory evaluation in which participants select the terms they consider apply at each moment from a list of attributes and deselect them when they no longer apply. The judges blindly tasted two different white wines in eight different glasses displayed with different label information related or not with terms associated with the minerality concept. In a second round, judges tried six glasses presented with the only information of the bottle’s price. In both tasting sessions, the used list of descriptors contained 44 terms, 16 of which were related to the attribute of minerality, 13 were considered antonyms of such a descriptor and 15 referred to extrinsic aspects. The results showed that consumers were not directly influenced by the label reported information or the bottle´s price when they described a wine as mineral. Finally, the statistical evaluation conducted by the CATA analysis divided the list of 44 used terms by their range of importance when a wine is described as mineral. The terms were divided into those that help to classify a wine as mineral and those that are antagonistic to this concept.

Strategies for the identification and sensory evaluation of volatile constituents in wine

Wine aroma, which stems from complex perceptual and cognitive processes, is initially driven by a multitude of naturally occurring volatile constituents. Its interpretation depends on the characterization of relevant volatile constituents. With large numbers of volatile constituents already identified, the search for unknown volatiles in wine has become increasingly challenging. However, the opportunities to discover unknown volatile compounds contributing to the wine volatilome are still of great interest, as demonstrated by the recent identification of highly odorous trace (µg/L) to ultra-trace (ng/L) volatile compounds in wine. This review provides an overview of both existing strategies and future directions on identifying unknown volatile constituents in wine. Chemical identification, including sample extraction, fractionation, gas chromatography, olfactometry, and mass spectrometry, is comprehensively covered. In addition, this review also focuses on aspects related to sensory-guided wine selection, authentic reference standards, artifacts and interferences, and the evaluation of the sensory significance of discovered wine volatiles. Powerful key volatile odorants present at ultra-trace levels, for which these analytical approaches have been successfully applied, are discussed. Research areas where novel wine volatiles are likely to be identified are pointed out. The importance of perceptual interaction phenomena is emphasized. Finally, future avenues for the exploration of yet unknown wine volatiles by coupling analytical approaches and sensory evaluation are suggested.

Statistical Modelization of the Descriptor “Minerality” Based on the Sensory Properties and Chemical Composition of Wine

When speaking of “minerality” in wines, it is common to find descriptive terms in the vocabulary of wine tasters such as flint, match smoke, kerosene, rubber eraser, slate, granite, limestone, earthy, tar, charcoal, graphite, rock dust, wet stones, salty, metallic, steel, ferrous, etc. These are just a few of the descriptors that are commonly found in the tasting notes of wines that show this sensory profile. However, not all wines show this mineral trace at the aromatic and gustatory level. This study has used the statistical tool partial least squares regression (PLS) to mathematically model the attribute of “minerality” of wine, thereby obtaining formulas where the chemical composition and sensory attributes act jointly as the predictor variables, both for white wines and red wines, so as to help understand the term and to devise a winemaking approach able to endow wines with this attribute if desired.

Minerality in Wine: Towards the Reality behind the Myths

Tasting minerality in wine is highly fashionable, but it is unclear what this involves. The present review outlines published work concerning how minerality in wine is perceived and conceptualised by wine professionals and consumers. Studies investigating physico-chemical sources of perceived minerality in wine are reviewed also. Unusually, for a wine sensory descriptor, the term frequently is taken to imply a genesis: the sensation is the taste of minerals in the wine that were transported through the vine from the vineyard rocks and soils. Recent studies exploring tasters’ definitions of minerality in wine support this notion. However, there are reasons why this cannot be. First, minerals in wine are nutrient elements that are related distantly only to vineyard geological minerals. Second, mineral nutrients in wine normally have minuscule concentrations and generally lack flavour. Results of reviewed studies overall demonstrate marked variability in both wine professionals’ and wine consumers’ definitions and sensory-based judgments of minerality in wine, although there is some consensus in terms of the other wine attributes that associate with the term mineral. The main wine composition predictors of perceived minerality involve a complex combination of organic compounds dependent on grape ripeness and/or derived from wine fermentations and redox status.

Sensory and chemical drivers of wine minerality aroma: An application to Chablis wines

The goal of this work was to evaluate the effect of vineyard position on the minerality of wines and to establish relationships between minerality scores, sensory descriptors and chemical composition. Sensory analyses included minerality rating and free description performed by wine professionals under two conditions: orthonasal olfaction alone and global tasting. Chemical characterization included analysis of major and minor volatile compounds, volatile sulphur compounds, mercaptans, metals, anions and cations. Results showed a significant effect of the river bank on wine minerality scores only in the orthonasal olfaction condition, samples from the left being more mineral than those from the right bank. Methanethiol, involved in shellfish aroma, was significantly higher in wines from the left (more mineral) than from the right bank. Contrary, copper levels, related to lower levels of free MeSH, and norisoprenoids, responsible for white fruit and floral aromas, were higher in wines from the right bank (less mineral).