Chemical and physical parameters of Andalusian honey: classification of Citrus and Eucalyptus honeys by discriminant analysis

Abstract

The characterization of two types of Andalusian unifloral honey (Citrus spp. and Eucalyptus spp.) was carried out on the basis of their physicochemical properties: moisture, hydroximetylfurfural, diastase, pH, free acidity, lactone acidity, electrical conductivity, glucose, fructose, sucrose, proline, invertase, glucose-oxidase, water activity and insoluble solids. All the data were statistically tested using analysis of variance, principal factor analysis (PFA) and stepwise discriminant analysis (SDA) with the aim of classifying the honeys and identifying the most significant parameters in the classification. Statistically, it was verified that the variables were different, depending on the type of honey. Of the six main factors obtained with a variance percentage of 78.95, it was the first one (free acidity, water, invertase, total sugars, electrical conductivity and solids) which explained the greater part of the variability (22.9%). The variables with the greatest discriminatory power were water activity and electrical conductivity with discrimination coefficients of −22.367 and 11.739, respectively. The overall proportion of accurately arranged samples was 96.6%.