Spectroradiometric color measurments were perofrmed at 26 regularly spaced points of a standard wine sampler into which 100 cc of wine were poured.Our goal is to describe the color changes occurring in this system,but not to propose a new method for wine-color measurments.Three samples of three different wines (red,rose and white)were studied.From experimental measurements,lines of constant lightness (L_(10)),chroma (C_(ab,10))and hue-angle (h_(ag,10))were plotted for each wine poured into the wine sampler,as well as lines of constant CIELAB color differences (DELTAE_(ab,10)),with repsect to a reference point placed at the axis of the wine sampler and at the zone with the greatest diameter.Considering different points of the wine sampler,the color attribute undergoing the greatest change was lightness (DELTAL_(10)about 16.0,15.0 and 11.0 for he red,rose and white wines,respectively),folowed by chroma (DELTAC_(ab,10)about 2.8,3.8 and 2.6 for the red,rose and white wines,respectively)and hue (DELTAH_(ab,10)lower than 1.0 for all the wines).Lightness variations were related mainly to the thickness differences between various zones of the wine sampler.Large color differences were found among the different points of the wine poured into the wine samler (about 20.0,21.0 and 14.0 CIELAB units,for the red,rose and white wines,respectively).Panels should be aware of these large color variations when wine is visually assessed using standard wine samplers.It should be concluded that a single color specification for a wine oured into a wine sampler gives incomplete information,but hue,whih is the maincolor attribute considered by observers,is nearly constant in the wine sampler.
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