Ultrasonic studies on thermodynamic parameters of honey

Viscosity, density and ultrasonic velocity of two honey samples (processed and unprocessed) was measured at different temperatures (20, 30, 40, 50, 60, 70 and 80°C) and thermodynamic parameters such as surface tension, adiabatic compressibility, acoustic impedance and intermolecular free length were derived from the measured values of density and ultrasonic velocity. The viscosity of honey samples was measured using Brookfield DV2T Viscometer, density using 25 ml specific gravity bottles and ultrasonic velocity using interferometer at a frequency of 3MHz. The viscosity, density, ultrasonic velocity, surface tension and acoustic impedance of processed honey was higher than that of unprocessed honey whereas adiabatic compressibility and Intermolecular free length was higher in unprocessed honey at any respective temperature. The value of all these thermodynamic parameters decreased with increase in temperature except adiabatic compressibility. Processed honey was more sensitive to temperature change than that of unprocessed honey. Log-log linear relation was found between the viscosity, density and ultrasonic velocity.