Anita Oberholster
Overview of the Red and White Wine Mouthfeel Wheels
Introduction• Tastes and tactile sensations• Matrix influence on bitterness + astringency• Phenol composition• Sensory properties of phenolics• Development of red wine mouthfeel wheel• Use of RMFW• Development of white wine mouthfeel wheel
Astringency Perception• Astringency described as “roughing”, “drying”
and “puckering”• Tactile sensation• Mechanism of astringency– Phenols bind with saliva proteins and precipitate– Stripping the mouth of lubrication “drying”– Texture effect of astringency could be due to
precipitated complexes or those in solution
• Astringency is dynamic process– Changes during ingestion and expectoration
Oberholster (2008)
Influences on Astringency + Bitterness
• Ethanol %– Decrease astringency perception– Increase bitterness perception
• Sugar content– Decrease bitterness– No influence on astringency, but more difficult to
perceive
Gawel (1998) Austr. J. Grape Wine Res. 4, p. 74-94
Influences on Astringency + Bitterness
• Other wine compounds such as organic acid have astringent sub-qualities themselves – Also contribute by lowering pH, phenol-protein
interactions
• Polysaccharides and proteins– Binds with tannins, reduce astringency
Gawel (1998) Austr. J. Grape Wine Res. 4, p. 74-94McRae and Kennedy (2011) Molecules 16, p. 2348-2364
Variation within Tasters• Effect of variation in salivary flow rate on
time-intensity scaling of bitterness and astringency– Low-flow; perceive max intensity later, more
intense, persistence longer
Oberholster (2008)
Astringency as a taste
• Average time-intensity curves for astringency in wine upon three successive ingestions: left 20s between ingestions; right 40s between ingestions. Sample uptake and swallowing are indicated by a star and arrow, respectively
Guinard et. al., 1986
Phenolics: Main Contributors to Astringency and Bitterness
• Main phenols (flavonoids) in red wine– Anthocyanins responsible for red color– Flavan-3-ols (ex. catechin, epicatechin)• Oligomers and polymers of flavan-3-ols, so called
proanthocyanidins (PA) or condensed tannins Fig 1
Anthocyanin
Figure 1: Proanthocyanidins
Extension units
Terminal unit
Background – phenols in wine• Extraction during wine making– Anthocyanins from skins• Early during fermentation (3-5 days)
– Seed PA (mDP ~ 10), higher % galloylation– Skin PA (mDP ~ 30), also contain
(epi)gallocatechin units• Increase extraction with temp, % EtOH
Sensory Properties of Flavanols
Gawel et al. (1998) Austr. J. Grape Wine Res.(6) 74
• Monomers more bitter than astringent
• Ratio of astringency to bitterness with mDP
Polymeric Phenols and Astringency• Sensory properties of proanthocyanidins
(PA)– Main contributors to bitterness and astringency– Ratio of astringency to bitterness increase with
mDP
• During wine maturation and ageing– Anthocyanins and PA polymerise with each
other by different mechanisms – Influenced by grape composition, presence of
wood (hydrolyzable) tannins
Gawel et al. (1998) Austr. J. Grape Wine Res.(6) 74; Vidal et al. (2003) J. Sci . Food Agric. (83) 564
Wine pigments
Direct condensation
Mateus et al., (2003) J. Agric. Food Chem. 51: 1919-1923; Reynolds (2010) Managing wine quality.
Flavanyl-vinyl-pyranoanthocyanin
Sensory properties of polymerization products
• How does polymerization reactions/products formed during wine aging influence Mouthfeel?
• Characterization of polymeric pigments– Comparing the polymeric pigment profile of 6
month old and 5 year old Syrah wine from the same vineyard• conc. of polymeric pigments, methylmethine and
vinyl-linked pigments• mDP of wine 4 10
– Development of the Mouthfeel wheelOberholster (2008)
Developing the Mouthfeel wheel• Panel of 14 tasters tasted 72 wines over 6
week period to derive a vocabulary– 6 months to 33 year old red wines (mean 4 yrs)– Mostly Australian Shiraz, Cab. Sauv. Pinot noir,
Grenach
• Another 75 red wines tasted to derive Mouthfeel terms not astringent-like– Influence Mouthfeel
• Investigate standards– Taste standards for astringency not practical
Gawel , Oberholster, Francis (2000) Austr. J. Grape Wine Res.(6) 203-207
Standards for Mouthfeel• Taste standards– Commercial tannins and other• Complex profiles• Tiring, influence subsequent perceptions• Carry-over effects
– Touch standards• Cutaneous sensations similar to those experienced in
the mouth
– Terms not represented by physical standards – well defined
Gawel , Oberholster, Francis (2000) Austr. J. Grape Wine Res.(6) 203-207
Mouthfeel wheel
Gawel , Oberholster, Francis (2000) Austr. J. Grape Wine Res.(6) 203-207
Mouthfeel Wheel Astringency
Gawel , Oberholster, Francis (2000) Austr. J. Grape Wine Res.(6) 203-207
Touch Standards Representing Tactile Sensations
Descriptor Touch standard
Talc Johnson baby powder
Satin Satin cloth
Plaster Gypsum powder
Chamois Moistened chamois
Silk High grade silk cloth
Velvet Velvet felt in direction of the nap
Suede Medium suede leather
Furry Short velour cloth
Fine emery paper 1000 grade emery paper
Corduroy Medium cord cloth
Abrasive 600 grade sandpaper
Hessian Carpet backing
Touch Standards Representing Tactile Sensations
SatinSilk
Suede Velvet
Sandpaper1000 grade
Fur (Furry)
Corduroy
Sandpaper600 grade (Abrasive)
Soft Suede(Chamois)
Burlap (Hessian)
Supplementary Definitions for Astringency Terms
Non-astringent Mouthfeel Terms
Gawel , Oberholster, Francis (2000) Austr. J. Grape Wine Res.(6) 203-207
Using the Mouthfeel Wheel (MFW)• Vidal (2003, 2004) fractionated tannins from
grape material – evaluate with MFW– Larger tannin more astringent and drying than
smaller tannin– Seed tannin more astringent (coarse, drying) than
skin tannin of equivalent size– Indicate ‘Coarseness’ and ‘dryness’ of
astringency increase with galloylation– Methylmethine-bridged flavanols more bitter
than similar tannins
Vidal et al. (2003) J. Sci . Food Agric. (83) 564Vidal et al. (2004) Food Qual. Pref. 15, 209-217.
Using the Mouthfeel Wheel (MFW)• Anthocyanins have no taste or tactile effect
(Singleton and Trousdale, 1992)
• Anthocyanins perceived astringency and “fullness” of model wine (Vidal et al., 2004b)
• Anthocyanins – more pure – no significant contribution to Mouthfeel (Vidal et al., 2004a)
• How do you explain differences between white wine and red wine?
Singleton and Trousdale (1992) AJEV 43, 63-70Vidal et al. (2004a) Food Qual. Pref. 15, 209-217Vidat et al. (2004b) Food Chem. 85, 519-525
Using the Mouthfeel Wheel (MFW)• How do you explain changes in Mouthfeel
observed during aging?– Could polymerization reactions explain changes in
Mouthfeel observed?– Increase mDP proanthocyanidins astringency– Formation of polymeric pigments?
Oberholster et al, (2009) Austr. J. Grape Wine Res. (15) 59-69Singleton and Trousdale (1992) AJEV 43, 63-70Vidal et al. (2004a) Food Qual. Pref. 15, 209-217Vidat et al. (2004b) Food Chem. 85, 519-525
Mouthfeel of different white wine treatments
Oberholster et al, (2009) Austr. J. Grape Wine Res. (15) 59-69
White free run juice
White free run juice + anth
Red wineWhite free run juice + white skins and seeds + anth
White free run juice + white skins + seeds
White free run juice + red skins and seeds
W WA WS WSA WRS RS
Mouthfeel Wheel
Oberholster et al, (2009) Austr. J. Grape Wine Res. (15) 59-69
Medium grain (Bentonite)
Coarse grain (Celite S45 filter aid)
Fine grain (Talcum powder)
Mouthfeel of different white wine treatments
Oberholster, et al.,(2009) Austr. J. Grape Wine Res. (15) 59-69
• W: white free run juice • WA: white free run juice + anth• WS: white free run juice + white skins and
seeds
• WSA: white free run juice + white skins and seeds + anth
• WRS: white free run juice + red skins and seeds• RS: red wine
Conclusion – RW-MFW• Using the MFW – small differences in phenol
content could be related to Mouthfeel differences– Anth increases astringency related terms, mainly
fine grain sub-attributes
• But MFW is difficult to use – needs extensive training
• Doubt wine consumers will be able to use this wheel to communicate in meaningful way
White Wine Mouthfeel Wheel• White wine elicit wide range of taste and
mouthfeel sensations• Pickering et al. (2008) evaluated 136 wines– Table, sparkling, dessert and fortified white wines– Using hierarchical wheel structure– Developed definitions and reference standards
• Tool to aid training and communication between wine professionals– Help define influence of viticultural and
enological variable on white wine quality
White Wine Mouthfeel Wheel
White Wine Mouthfeel Wheel• Some major difference between the white
and red mouthfeel wheel– Contains taste parameters– Avoided terms related to flavor even though
observed retro-nasally– Inclusion of “time dimension” in the wheel– Descriptors are ordered clockwise starting at 12’
noon in approx order of perception and intensity perceived• RMFW has no intensity levels build in
Pickering and DeMiglio (2008) J. Wine Res. 19 (1) p. 51-67
White Wine Mouthfeel Wheel• EtOH %– Elicit tactile sensations • Heat/irritation• Astringent-like drying• EtOH enhance lubricity of oral cavity – reducing the
perception of roughness
• Glycerol– Could contribute to perceived viscosity, reducing
roughness, decreasing astringency
• Polysaccharides can also potentially contribute in similar way as glycerolGawel et al. (2007) Austr. J. Grape Wine Res. 13, p. 38-45
Pickering and DeMiglio (2008) J. Wine Res. 19 (1) p. 51-67
White Wine Mouthfeel Wheel• Discrete sensations
⁻ Used RMFW as reference so some similar terms⁻ Diffr groupings of sensations
White Wine Mouthfeel Wheel• Discrete sensations
⁻ Surface smoothness terms have levels associated
⁻ Satin, silk and chamois are different levels of smoothness⁻ Particulate terms are grouped under surface smoothness
White Wine Mouthfeel Wheel
White Wine Mouthfeel Wheel• Integrated sensations
⁻ These product are associated with sparkling wines⁻ Seems body and weight related
White Wine Mouthfeel Wheel• Integrated sensations
⁻ These product are associated with sparkling wines⁻ Seems body and weight related
Integrated sensations
White Wine Mouthfeel Wheel• Usefulness of WMFW is still unknown• Due to different WMFW and RMFW concepts– Using both wheels will be confusing– Too many complex or integrated terms which is
not well defined– Both wheels can be adapted for personal use– Simplified and clarified further
Thank you• Funding (GWRDC)• Mouthfeel panel
Elizabeth WatersGraham JonesPatrick IlandLeigh FrancisRichard Gawel
Karen BlockLinda BissonLucy JosephKay Bogart
Touch Standards Representing Tactile Sensations
Satin Silk Suede VelvetSandpaper1000 grade
Fur (Furry)
Soft Suede(Chamois)
Sandpaper600 grade (Abrasive)
Burlap (Hessian)Corduroy
Mouthfeel Standards and Definitions
Satin SilkSuede Velvet
Sandpaper1000 grade
Fur (Furry)
Soft Suede(Chamois)
Sandpaper(Abrasive)Burlap (Hessian)
Corduroy