COMPARISON BETWEEN THE TRISTIMULUS MEASUREMENTS YXY AND L-ASTERISK A-ASTERISK B-ASTERISK TO EVALUATE THE COLOR OF YOUNG RED WINES

The chromatic characteristics of 10 young red wines elaborated in the region of Murcia (Spain) were determined. The colour measurements obta ined using the Yxy and CIELAB systems were compared. The calculation o f dominant wavelength and its representation in the C.I.E. chromatic d iagram revealed almost imperceptible differences in the wines classifi ed, while La*b* values achieved a much better differentiation. L* and a gave an accurate definition of the wines. L* ranged from 37 to 72 while a varied between 23 and 54. One wine sample was clearly differe nt from the others, showing the highest degree of lightness (L), the lowest redness (a) and the lowest saturation (C*). The graphical repr esentation of metric lightness difference (Delta L) against metric ch roma difference (Delta C) showed the difference in colour between the wines analyzed. Wine number 1 showed the deepest colour followed by w ines numbered 9 and 5, while wine number 7 was very pale. The data obt ained were correlated by means of the corresponding matrix of Spearman correlation coefficients, which revealed that the highest correlation s existed between L and colour intensity and between L* and ionised a nthocyanin content.