Effects of Sugar Content and Temperature on Rheology and Microrheology of Israeli Honey

摘要

The rheological properties of selected Israeli honeys were evaluated using both rheology and microrheology. Most honeys are Newtonian; their viscosity ranges over 3–4 orders of magnitude and the water content is typically between 13–29%. The viscosity of honey is determined by the temperature, the relative amount of water/sugar, and the molecular chain length of sugars present in the honey, which is correlated to the origin of the honey. Effects of temperature and origin of the honey were determined with rheology and compared to microrheology to distinguish any local heterogeneity. Rheological measurements were correlated with the moisture content, as determined by refractometry. After the base-line behavior had been established, sugars were added to floral-origin standard and reduced-calorie honeys, to determine the effect of supplementary sugar on the rheology. This approach may be used to determine whether sugar content of a honey, or similar materials, has been altered; this could be especially valuable for non-homogeneous materials, such as jams with solid particles.