Classification of Southern Tunisian honeys based on their physicochemical and textural properties

This study investigated the physicochemical, rheological and textural properties of nine types of honey from different regions of southern Tunisia. Principal component and cluster analyses were used to classify the honeys into groups. The physicochemical results (water, proteins, total soluble solids, pH, free acidity, water activity, electrical conductivity, invertase activity, Hydroxymethylfurfural (HMF), vitamin C, lycopene and anthocyanins) were in accordance with those of the standards Established by the Codex Alimentarius. The invertase activity varied from 62.58 units/kg to 110.24 units/kg. The HMF values of the different types of honey ranged from 11.48 mg/kg in prickly pear honey to 25.56mg/kg in heather honey. Anthocyanin contents, lycopene and vitamin C contents ranged between 8.38 and 24.86 μg/L, 1.08 to 6.17 mg/kg and 30.71 to 129.38 mg/kg, respectively. The flow test confirmed the Newtonian behavior of all honeys, and their textural properties had very high extrusion forces varying from 113.50 g to 131.05 g. Cluster analysis (CA) and the biplot generated through PCA recognized four groups of honeys based on either the physicochemical parameters or textural attributes and only three groups based on color and sugar.