Interrelationships among electrical conductivity, refractive index and viscosity of honey

Abstract

The reported work was undertaken to make a systematic study of the physical parameters of raw honey like electrical conductivity, refractive index and viscosity to explore interrelationships among these. All the measurements were taken at different temperatures (20, 30, 40, 50, 60, 70°C) and concentrations (100, 90, 80, 70, 60 and 50%). The electrical conductivity increased linearly both with temperature and upon dilution. The refractive index decreased linearly with temperature and was found to increase linearly with concentration of honey. The viscosity of honey decreased exponentially both with the increase of temperature and with decrease of concentration. The Arrhenius mathematical model was applied to establish the temperature dependence of honey viscosity and thus used for the determination of its activation energy. The honey with highest viscosity values displayed the highest value for activation energy. The studied parameters were found to vary significantly with temperature for all honey concentrations. The regression equations modelling the relationship of electrical conductivity with viscosity and refractive index values of honey were found to have high correlation coefficients (>0.93).