HONEYDEW HONEY ADULTERATION: E-TONGUE AND PHYSICO-CHEMICAL ANALYSES

Abstract

The aim of this study is to evaluate the usefulness of the e-tongue and physico-chemical analyses (pH, electrical conductivity (EC), colour parameters (L*, a*, b*, chroma and hue angle)) for honeydew honey adulteration detection. For this purpose the honeydew honeys have been adulterated with inverted sugar and malt wort in different percentages (5, 10%, 20%, 30%, 40% and 50% respectively). The e-tongue used consisted of three electrodes: the reference electrode (Ag/AgCl), counter electrode (Glassy Carbon Electrode Rod - GC) and working electrodes (Ag and Au). The measurement has been made using the cyclic voltammetry. The addition of malt wort and inverted sugar influenced all the physico-chemical and e-tongue parameters. The addition of malt wort decreased the magnitude of the colour parameters (L*, a* and b*) and pH, and increased free acidity and electrical conductivity. The addition of inverted sugar increased the colour parameters’ values and free acidity and decreased the electrical conductivity and pH. According to the principal component analysis (PCA) the samples with 5% and 10% inverted sugar and 5% malt wort are placed near to the authentic samples, so we can conclude that the samples have physico-chemical and e-tongue parameters closed to the authentic honeydew honey.