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p r a c t i c a l w i n e r y & v i n e ya r d J a n U a r y 2 0 1 5 25 W I N E M A K I N G derived for quantifying discrete oral sen- sations elicited by white wine. Discussion In development of the RWMW, sort- ing tasks by the panel and subsequent cluster analysis were used to assist in categorization of astringency terms. This approach was not used in our study, assuming that the validity of the group- ings developed by R. Gawel et al. would hold for white wine. 12 Focus-group techniques were used extensively where the experienced panel played a dominant role in development and refinement of the terminology, cat- egorization of the descriptors and devel- opment of reference standards. There is significant overlap between the white and red wine mouthfeel wheel lexicons, definitions and grouping of sensations, which is to be expected given panel to assess the utility and discrimina- tory properties of the wheel, and to make minor adjustments to definitions, stan- dards and evaluation methods. Intensity scales were employed for discrete descrip- tors, while presence/absence ratings were used for integrated descriptive terms. Results Figure I shows the final lexicon, visual- ized as a hierarchical, segmented wheel (see page 22). The wheel is divided into 33 discrete sensations and 21 integrated percepts, consisting of more than one sensation or concept. Further ordering of the tiers is based on groupings of increas- ingly similar attributes, similar to the structuring used by R. Gawel et al. 12 Outer-tier terms are the specific oral qualities that are used to score and describe white wine. Segments are color- coded to facilitate ease of use by group- ing attributes together that belong to the same oral quality/ dimension or that are elicited by the same wine style. Attributes that were predominantly elicited by sparkling wines are color- coded brown, and taste qualities are yel- low. Non-taste sensations are deep green, while those that pertain to surface tex- ture attributes are light green. Integrated qualities, other than those elicited by sparkling wines, are purple. Table I lists outer-tier terms derived by the panel to describe discrete sensations, along with their definition, intensity terms and the type of reference standard used. Table II gives the composition of the oral and manual reference standards for discrete sensations and a descrip- tion of how they are used or evaluated. Table III shows the same information for integrated sensations. Figure II provides representative examples of the scales Outer-tier descriptors Final composition of standards Evaluation protocol Sweetness 30 g/L sucrose (Sigma-Aldrich) in water Swirl sample around mouth (corresponds to anchor term sweetness at 2.5 cm) Acidity 1,2,3 and 4 g/L of tartaric acid (Fischer ™ ) in aqueous solution Swirl sample around mouth (corresponds to "Levels 1,2,3 and 4", respectively) Saltiness Moderate = 1.5 g/L NaCl in aqueous solution Swirl sample around mouth Tingle 'Slight' = Moderately carbonated mineral water (bottle cap Swirl sample around mouth partially unscrewed for 24 hrs to release some CO 2 ) 'Tingle' = Moderately carbonated mineral water opened immediately prior to serving Weight a concentration series of 0.5 g/L, ('light'), 1 g/L ('moderate') Take equal volume of sample and and 2 g/L ('heavy') of carboxymethyl cellulose (Sigma-Aldrich) hold in mouth in aqueous solution Viscosity a concentration series of 0 g/L ('thin'), 0.5 g/L, 1 g/L, 2 g/L, and Take equal volume of sample and 3 g/L ('thick') of carboxymethyl cellulose (Sigma-Aldrich) in move from side to side in mouth aqueous solution Warm and hot Warm: 13% v/v ethanol (LCBO, Canada) solution Swirl sample around mouth Hot: 15% v/v ethanol (LCBO, Canada) solution Silk, satin, and chamois 2 x 3.5 cm strips of silk fabric, satin fabric, and chamois cloth Silk: rub the bottom 'shiny' side of (all Fabricland ™ , St Catharines) the fabric between your forefinger and thumb moving with the nap; Satin: rub with your thumb the shiny 'top' side of the fabric moving with the nap; Chamois: rub the smoother side of the cloth between your forefinger and thumb Fine and medium emery 2 x 3.5 cm strips of fine and medium emery paper Hold the emery paper firmly (respectively, 600 grit and 220 grit Norton ® all purpose sandpaper, between forefinger and thumb Home Dept ™ , St Catharines) while rubbing the sample back and forth with thumb Sharp single sheet of heavily crinkled aluminium foil paper rolled into Roll aluminium foil ball between 3 cm diameter ball the palms of your hands Talc, chalky, plaster and grainy Talc powder: Johnson and Johnson ® baby powder Rub each standard between thumb Chalk: standard blackboard chalk and fingers Plaster: dry gypsum powder Grainy: sand from Vanwagners beach, Hamilton Ontario Baby oil, sunflower oil and Baby oil ('light' mouthcoat): Johnson and Johnson ® baby oil Insert finger in oil and smear olive oil Sunflower oil ('moderate' mouthcoat): Unico ® sunflower oil between forefinger, middle finger Olive oil (' heavy' mouthcoat): Bertoli ® extra virgin olive oil and thumb in a circular motion Bitterness 0.05g/L of quinine sulphate in aqueous solution = Swirl sample around mouth moderate bitterness intensity Dry and parching A concentration series of 0.05 g/L, 0.1 g/L, 0.25 g/L and Swirl sample around mouth 0.5 g/L alum sulphate in aqueous solution, representing low, medium, high, and parching drying sensations, respectively Table II: Composition of oral and manual reference standards and their application for discrete sensations