Colour as a driver of Pinot noir wine quality judgments: An investigation involving French and New Zealand wine professionals

Enhancing cider quality through co-fermentation with acid protease and esterase-producing Metschnikowia species and Saccharomyces cerevisiae

BACKGROUND

To date, cider production has primarily relied on Saccharomyces cerevisiae. Introducing novel non-Saccharomyces yeasts can enhance the diversity of cider properties. Among these, the Metschnikowia genus stands out for its ability to produce hydrolytic enzymes that may impact the sensorial and technological properties of cider. This study focused on evaluating the impact of three Metschnikowia species - Metschnikowia koreensis (Mk), M. reukaufii (Mr), and M. pulcherrima (Mp) - which exhibit acid protease and esterase activity, on the quality enhancement of cider.

RESULTS

The research findings indicate that the overall quality of cider produced through co-fermentation with these species surpassed that of cider fermented with mono-fermentation of S. cerevisiae (Sc). The cider fermented with the Sc + Mk combination exhibited the lowest levels of harsh-tasting malic acid and higher levels of softer lactic acid. Sensory array analysis also demonstrated that the Sc + Mk fermented cider exhibited high sensor response values for compounds contributing to a complex overall olfactory composition and richness. Furthermore, the Sc + Mk fermented cider exhibited the highest total quantity and variety of volatile organic compounds (VOCs). Specifically, the concentrations of phenethyl alcohol, 3-methyl-1-butanol, ethyl octanoate, and decanoic acid were notably elevated in comparison with other groups.

CONCLUSION

This study illustrates that Metschnikowia species, particularly M. koreensis, show significant potential as starters for cider due to their various technological properties, including acidity modulation, aroma enhancement, and color improvement. The findings of this study provide a foundation for improving cider quality by co-fermenting S. cerevisiae with innovative starter cultures. © 2024 Society of Chemical Industry.

Inter-regional characterisation of New Zealand pinot noir wines: Correlation between wine colour, monomeric and polymeric phenolics, tannin composition, antioxidant capacity, and sensory attributes

A total of 116 New Zealand Pinot Noir wines from Central Otago (CO), Marlborough (MLB), and Martinborough (MTB) were analysed for colour, monomeric and total phenolics, antioxidant capacity, and tannins using colourimetric and HPLC methods. Correlations among chemical compositions and analytical techniques were examined. Additionally, a sensory study assessed wine colour and five mouthfeel attributes. Discriminant analyses revealed significant regional characteristics. CO wines displayed unique monomeric anthocyanin profiles and were perceived as softer on the palate. MLB wines showed higher residual sugar but lower colour intensity and tannin concentration. MTB wines exhibited higher colour and robust mouthfeels, linked to higher colour absorbances, polymeric pigments, and tannins. Mouthfeel attributes correlated significantly with wine total phenolics, MCP and HPLC tannin measurements, and the degree of tannin polymerisation (mDP). The combined chemical and sensory data enhanced regional differentiation, demonstrating the importance of integrating comprehensive chemical measurements with sensory evaluations for thorough wine classification.

Factors explaining differences in wine experts' ratings: The case of gender, credentials, occupation and peer effects

The aim of this article is to better understand why experts give different scores to the same wines in identical tasting environments. This research focuses on the personal characteristics of experts (or judges), such as their gender, industry credentials, and occupation within the wine industry, and examines how judges respond to their peers' characteristics. Using a dataset of 5,395 wines judged in the 2022 International Wine and Spirits Competition, we analyse 18,224 scores from different judges. We estimate a series of grade equations at the judge level to understand why a same wine received different scores from judges. A first model makes use of the panel structure of the dataset, incorporates wine fixed effects, and focuses on the personal characteristics of judges. A second model encompasses characteristics of the judging team, without the inclusion of wine fixed effects. At large, on-trade buyers give lower scores than off-trade buyers, as well as female judges compared to male ones. While credentials are not a very significant factor per se, they do have the potential to generate peer effects. Judges tend to be more generous in their assessments when they are assigned to a team with Master of Wine judges. Conversely, they are also consistently more severe when the number of female judges on the team increases. Estimation results converge across sub-datasets, with the exception of sparkling wines. Given the feminisation of the wine industry, in terms of producers, consumers, and experts, the severity of female judges could be beneficial in terms of social welfare.

Understanding the relationship between tropical fruit aroma, acceptance, and emotional response in chardonnay wines

Tropical fruit aromas are prominent in many white wines. The purpose of this work was to determine if winemaking practices could impact the tropical fruit aromas in the Chardonnay wines and how those aroma differences influenced wine consumers acceptance and emotional responses. Four treatments were tested at varying fermentation temperature gradients and skin contact times: control fermentation at 13 °C with no skin contact (Control), fermentation at 13 °C with 18 h of skin contact (SC), fermentation temperature gradient by time (20 °C for 4 days then reduced to 13 °C) with no skin contact (FG), fermentation temperature gradient by time with 18 h of skin contact (SCFG). Acceptance, using a 7-point hedonic scale, showed there was not a significant difference between treatments. Emotional response, using a 5-point Rate-All-That-Apply (RATA) scale, showed significant differences for 'calm' and 'disgusted' emotions. Check-all-that-apply (CATA) for aroma descriptors showed that Control is described using aromas of passionfruit, lychee, and pome fruit; SC had aromas of grapefruit and floral; FG was described as having melon, lychee, and pineapple aromas; and SCFG was described with aromas of lemon/lime, mango, and guava. Positive emotions were associated with fruity aromas in the wines, although no difference in acceptance was found. Winemaking treatments impacted the aroma profile of chardonnay wine, with tropical aromas evoking positive emotions in consumers. The relationship between specific aromas and consumers emotion responses can be an important tool to understand the factors behind a wine's success or lack thereof. Moreover, it can help with the creation of new wine products.

Fine wine recognition and appreciation: It is time to change the paradigm of wine tasting

Wine quality maybe understood under two perspectives: (a) commercial quality, intended to satisfy overall consumers, and (b) fine wine quality, aimed at achieving a product with aesthetic value. The current food sensory techniques (e.g. Descriptive Analysis) have been successfully applied to develop wines accepted worldwide and characterized by pleasant sweetish flavours and smooth mouthfeel. On the contrary, these techniques are not suited to characterize fine wines given their dependence on sensory properties with aesthetic value. The conventional tasting approaches follow the sequence of vision, smell (orthonasal), taste and mouthfeel, ending by an overall evaluation. The sensory descriptors tend to be analytic (e.g. different aromas and tastes) or synthetic (e.g. body, structure) and the quality judgement is left for the final step. Some synthetic attributes may have an aesthetic significance (e.g. complexity, harmony, depth) and are more valued when the analytic or synthetic descriptors are highly praised (e.g. oakiness, silkiness, body, minerality). Consequently, these highly praised attributes are regarded as surrogates of fine wine quality. However, commercial wines are frequently judged of higher quality than fine wines irrespective of the taster expertise. We argue that the conventional sensory analysis sequence makes the overall evaluation secondary in relation to the previous analytical steps blurring the assessment of wine's aesthetic properties. Probably due to top-down processing, the initial evaluation of colour or flavours governs the final overall quality evaluation that may be inconsistently rated. Then, to promote the recognition of fine wines, tasting should begin by first acknowledging the aesthetic properties and only proceed to the analytical steps if necessary. A tasting method is proposed to consumer educational programs where emotional responses are used to explain the differences between commercial and fine wine styles. Furthermore, cultural aspects should be included to appreciate the wholeness of wine. Hopefully, this holistic perspective would turn wine appreciation more approachable and facilitate the recognition of fine wines among consumers, increasing their appreciation and enjoyment.

Sequential inoculation of flocculent Torulaspora delbrueckii with Saccharomyces cerevisiae increases color density of Pinot Noir wines

Pinot noir grapes require careful management in the winery to prevent loss of color density and promote aging stability. Winemaking with flocculent yeast has been shown to increase color density, which is desirable to consumers. This research explored interspecies sequential inoculation and co-flocculation of commercial yeast on Pinot noir wine color. Sedimentation rates of six non-Saccharomyces species and two Saccharomyces cerevisiae strains were assayed individually and in combination. The most flocculent pairings, Torulaspora delbrueckii BIODIVA with S. cerevisiae RC212 or VL3, were used to ferment 20 L Pinot noir must. Sequential fermentations produced wines with greater color density at 420 + 520 nm, confirmed by sensory panel. Total and monomeric anthocyanin concentrations were decreased in sequentially fermented wines, despite being the main source of red wine color. BIODIVA adsorbed more anthocyanins than S. cerevisiae, indicating a greater number of cell wall mannoproteins in flocculent yeast, that could then result in a later release of anthocyanins and enhance copigment formation in red wines.

The meaning of the word elegance as a wine descriptor: Effect of expertise and wine type

The aim of the present study was to investigate the concept of elegance in wine as a function of (i) domain-specific expertise, and (ii) wine type, more specifically as applied to still wine and to sparkling wine. One hundred and fifty participants, classified into five categories depending on their wine-relevant expertise, completed an online questionnaire aimed at inducing verbal responses concerning their cerebral representations of elegance as applied to still wines and sparkling wines. The five participant categories comprised four expert groups, namely wine producer [30], wine writer/critics [30], sommeliers [30], wine merchant/seller [30], and a novice group of wine consumers [30]. Results showed that both professional and novice participants found the concept of 'elegance' applicable to both still wine and sparkling wine, evoking words and terms with reasonable consistency overall. Differences were found, both between participant groups and between wine types. After categorisation, significant differences between participant categories were found for two of the ten categories of words elicited for both inducing expressions. Extrinsic quality and intrinsic quality were significantly different across occupational categories for 'elegant in relation to wine'. Extrinsic quality was noticeably higher for consumers than the other participants while intrinsic quality appears more important to conceptualisations of wine elegance for wine writers/critics than it is for the other groups of participants. Concerning 'elegance in sparkling wine', extrinsic quality also showed significant differences across participant categories, being highly evoked by producers and merchants/sellers. The category context/analogy was significantly higher in consumers' associations and interestingly, lower in writer/critics' associations. These results support the notion that application of the term elegance as a wine descriptor is seen as appropriate by both wine professionals and wine consumers, suggesting that the term elegant when applied to either still or sparkling wine evokes a concept that is not idiosyncratic but that has a central structure shared by many wine professionals and consumers, the core of this structure including terms smooth, balanced, refined and complex.

In-mouth attributes driving perceived quality of Pinot noir wines: Sensory and chemical characterisation

We investigated perception of mouthfeel in Pinot noir wines and its physicochemical determinants. Seventeen wine professionals judged 18 Pinot noir wines via two tasting tasks, Descriptive Rating and Directed Sorting, the latter based on perception of in-mouth attributes. Selected chemical measures of the same 18 wines were determined. Sensory results demonstrated that mouthfeel attributes driving high quality were smoothness/silky/velvety, volume/fullness/roundness, overall body, and viscosity/mouth-coating, while the taste of bitterness and perceived tannin harshness drove low quality judgments. Perceived astringency and expressions of tannin (e.g., soft; harsh; fine) drove sorting behaviour of participants. Partial least squares regression (PLSR) was used to associate perceived in-mouth phenomena and chemical composition. The phenolic profile, in particular tannin concentration and structure, was the most important predictor of astringency and its sub-components. These results have important implications for wine producers aiming to enhance perceived quality in their Pinot noir wines.

Investigating the Relationship between Perceived Meal Colour Variety and Food Intake across Meal Types in a Smartphone-Based Ecological Momentary Assessment

Although most people are aware of the health benefits of consuming sufficient amounts of fruit and vegetables, many do not adhere to current dietary recommendations. Recent studies have suggested meal colour variety as an intuitive cue for healthy and enjoyable lunch meal choices. The present study extends this research by testing the “colourful = healthy” association across meal types. Using smartphone-based Ecological Momentary Assessment, 110 participants recorded 2818 eating occasions over a period of eight days. For each eating occasion, a picture, a short written description of the meal, the meal type (breakfast, lunch, afternoon tea, dinner, snack) and the perceived meal colour variety were recorded. Foods were classified into seven food groups based on the pictures and descriptions. Data were analysed using multilevel modelling. For all meal types except afternoon tea which did not include vegetables, perceived that meal colour variety was positively related to vegetable consumption (bs ≥ 0.001, ts ≥ 3.27, ps ≤ 0.002, quasi-R²s ≥ 0.06). Moreover, perceived meal colour variety was negatively associated with sweets consumption for breakfast, dinner and snacks (bs ≤ −0.001, ts ≤ −2.82, ps ≤ 0.006, quasi-R²s ≥ 0.01). The “colourful = healthy” association can be generalized across meal types and thus may be a promising strategy to promote a healthier diet.

Metabolomics Approach to Assess the Relative Contributions of the Volatile and Non-volatile Composition to Expert Quality Ratings of Pinot Noir Wine Quality

Wine flavor and quality are determined by the assessment of multiple sensory stimuli, including aroma, taste, and mouthfeel. It is therefore important to consider the contribution of as many metabolites as possible when attempting to relate wine composition to quality. In this study, partial least squares regression of the volatile (untargeted headspace solid-phase microextraction coupled with gas chromatography time-of-flight mass spectrometry), non-volatile (untargeted reverse-phase ultra-high-performance liquid chromatography mass spectrometry), and combined metabolite profiles were used to predict Pinot Noir wine quality ratings as assessed by experts. Non-volatile metabolite profiles predicted wine quality ratings better than volatile metabolite profiles, suggesting that the non-volatile composition of Pinot Noir wines contributes to quality perception to a greater extent than the volatile composition. This was underscored by descriptive sensory analysis, which found that taste and mouthfeel attributes were better correlated with wine quality ratings than aroma attributes. Important predictors of Pinot Noir wine quality were also characterized. Some new relationships between wine metabolites and quality ratings were found: dipeptides and unsaturated fatty acids were positively related to Pinot Noir wine quality, while N-(3-methylbutyl)acetamide and xanthine were negatively associated.

Exploring the Typicality, Sensory Space, and Chemical Composition of Swedish Solaris Wines

The Swedish wine industry has exponentially grown in the last decade. However, Swedish wines remain largely unknown internationally. In this study, the typicality and sensory space of a set of twelve wines, including five Swedish Solaris wines, was evaluated blind by Swedish wine experts. The aim of the work was to evaluate whether the Swedish wine experts have a common concept of what a typical Solaris wines should smell and taste like or not and, also, to bring out more information about the sensory space and chemical composition of Solaris wines. The results showed a lack of agreement among the wine experts regarding the typicality of Solaris wines. This, together with the results from the sensory evaluation, could suggest the possibility of different wine styles for Solaris wines. From a chemical perspective, the global volatile profile showed a larger variability between individual wines than between Solaris and non-Solaris. However, 4MMP, ethyl propionate, ethyl 2-Methyl propanoate, and diethyl succinate were significantly higher in Solaris wines. Concerning non-volatile compounds, the results showed a significant discrimination between Solaris and non-Solaris wines, the former being characterized by higher ethanol %, Mg, succinic acid, tartaric acid, and sucrose levels.

Wine psychology: basic & applied

Basic cognitive research can help to explain our response to wine, and the myriad factors that affect it. Wine is a complex, culture-laden, multisensory stimulus, and our perception/experience of its properties is influenced by everything from the packaging in which it is presented through the glassware in which it is served and evaluated. A growing body of experiential wine research now demonstrates that a number of contextual factors, including everything from the colour of the ambient lighting through to background music can exert a profound, and in some cases predictable, influence over the tasting experience. Sonic seasoning - that is, the matching of music or soundscapes with specific wines in order to accentuate or draw attention to certain qualities/attributes in the wine, such as sweetness, length, or body, also represents a rapidly growing area of empirical study. While such multisensory, experiential wine research undoubtedly has a number of practical applications, it also provides insights concerning multisensory perception that are relevant to basic scientists. Furthermore, the findings of the wine research are also often relevant to those marketers interested in understanding how the consumers' perception of any other food or beverage product can potentially be modified.

A review on the aroma composition of Vitis vinifera L. Pinot noir wines: origins and influencing factors

Vitis vinifera L. Pinot noir still wines are some of the most popular and expensive red wines in the world. Several research articles are reported in literature concerning the impacts of viticultural and enological practices, and vineyard location, on Pinot noir still wine aroma. This review summarizes the previous and latest literature pertaining to volatile compounds including esters, higher alcohols and C₁₃-norisoprenoids, and their effect on Pinot noir wine perceived aroma. Their origin and behavior are discussed, as well as their role in regional differentiation. The first part of this review paper presents an overview of volatile compounds that are usually found in Pinot noir still wines at concentrations higher than their odor detection threshold. The second part deals with studies pertaining to human inputs that impact on Pinot noir wine aroma profile such as viticulture and winemaking interventions. The role of the vineyard site is also revised. This review concludes by considering what further opportunities are available to researchers in this field for greater control over Pinot noir wine quality outcomes.

Drinking through rosé-coloured glasses: Influence of wine colour on the perception of aroma and flavour in wine experts and novices

Wine colour carries a myriad of meanings regarding the provenance and expected sensory qualities of a wine. That meaning is presumably learnt through association, and part of a wine taster's skill comes from being able to decode information that can be discerned in subtle variations in the colour of the wine that they drink/evaluate. However, reliance on colour means that wine tasters, especially experts, often exhibit colour-induced olfactory biases. The present study assesses how wine colour - specifically the pink hue of rosé wines - can influence both the perceived aroma and flavour in a large sample of wine novices and experts. Participants (N = 168) tasted three wines - a white wine (W), a rosé wine (R), and the white wine dyed to match the rosé (Ŕ) - and freely selected three aroma and three flavour descriptors from a list. They also rated wine liking, flavour intensity, and description difficulty for each wine. Linguistic analysis demonstrated that those with wine tasting experience judged Ŕ to be much more similar to R than to W, even though Ŕ and W were the same. Moreover, red fruit descriptors were attributed to both R and Ŕ, especially in terms of flavour. Quantitative ratings revealed that Ŕ was liked less than W or R, and participants found it more difficult to describe Ŕ than R. These results demonstrate that while participants found the dyed rosé somehow different from the undyed wines, they nevertheless used the red fruit terms to describe its aroma and flavour. The implications of such results in terms of cognitive representations of wine and the role of sensory expectations are discussed.

Expectation or Sensorial Reality? An Empirical Investigation of the Biodynamic Calendar for Wine Drinkers

The study’s aim was to investigate a central tenet of biodynamic philosophy as applied to wine tasting, namely that wines taste different in systematic ways on days determined by the lunar cycle. Nineteen New Zealand wine professionals tasted blind 12 Pinot noir wines at times determined within the biodynamic calendar for wine drinkers as being favourable (Fruit day) and unfavourable (Root day) for wine tasting. Tasters rated each wine four times, twice on a Fruit day and twice on a Root day, using 20 experimenter-provided descriptors. Wine descriptors spanned a range of varietal-relevant aroma, taste, and mouthfeel characteristics, and were selected with the aim of elucidating both qualitative and quantitative aspects of each wine’s perceived aromatic, taste, and structural aspects including overall wine quality and liking. A post-experimental questionnaire was completed by each participant to determine their degree of knowledge about the purpose of the study, and their awareness of the existence of the biodynamic wine drinkers’ calendar. Basic wine physico-chemical parameters were determined for the wines tasted on each of a Fruit day and a Root day. Results demonstrated that the wines were judged differentially on all attributes measured although type of day as determined by the biodynamic calendar for wine drinkers did not influence systematically any of the wine characteristics evaluated. The findings highlight the importance of testing experimentally practices that are based on anecdotal evidence but that lend themselves to empirical investigation.