INFLUENCE OF CHEMICAL COMPOSITION AND TEMPERATURE ON HONEY PHASE ANGLE

Abstract

Honey is a complex material which exhibits a viscoelastic behavior under oscillatory testing. The rheological behavior of honey is influenced by moisture content, concentration and by the temperature (all the rheological parameters are decreasing with the increasing of the temperature). This article is about the influence of chemical composition (fructose, glucose, sucrose, moisture content) and temperature on the honey phase angle. The honey is meeting the Codex Alimentarius requirements regarding moisture content. The sum of fructose and glucose concentrations was 60 g/100 g in agreement with CE directive 2001/110/CE. The phase angle was measured at 30, 35, 40, 45 and 50 °C; the viscous component is maxim at low temperature (in the study case at 30 -45 °C). It can be observed that at 30 °C, 35 °C, 40 °C and 45 °C, the phase angle evolution is not influenced by the frequency applied; the phase angle is changing a little with the frequency. At 50 °C, the phase angle is strongly influenced by the frequency, is decreasing its value proportionally with frequency.The suitable precidtion of the phase angle with temperature and chemical composition has been observed using the 3^rd grade polynomial model with variables; the model achivied has reached a regression coeffiecient (R²) 0.9915.