CLASSIFICATION OF SPANISH UNIFLORAL HONEYS BY DISCRIMINANT-ANALYSIS OF ELECTRICAL-CONDUCTIVITY, COLOR, WATER-CONTENT, SUGARS, AND PH

To ascertain the most discriminant variables for seven types of Spanis h commercial unifloral honeys, stepwise discriminant analysis was perf ormed. Fifteen parameters [pH; water content; electrical conductivity; x, y, and L, chromatic coordinates from the CIE-1931 (xyL) color spac e; fructose; glucose; sucrose; maltose; isomaltose; maltulose; kojibio se; and the fructose/glucose and glucose/water ratios] were considered . The studied honey types were rosemary, citrus, lavender, sunflower, eucalyptus, heather, and forest. The most discriminant variables, as s elected by the multivariate program, were electrical conductivity, col or (x, y, L), water content, fructose, and sucrose. All sunflower, euc alyptus, and honeydew honey samples and >90% of the samples from the r emaining honey types were correctly classified by using the classifica tion functions devised by the program. The overall proportion of accur ately arranged samples was 95.7%. Results were validated by the ''jack knifed'' procedure and showed that electrical conductivity, color, wat er content, fructose, and sucrose are highly useful parameters to clas sify unifloral honeys, although microscopical analysis of honey sedime nt remains the fundamental tool.