Honey Adulterated with Glucose Syrup: Rheological Modeling

Abstract

Honey's reputation for its various both nutritional and medicinal benefits and pleasant taste ensures a sustained high demand for the product all over the world. However, honey supply is quite limited and seldom meets the demand, and consequently the product commands a relatively high price and is exposed to adulteration and imitation. Honey was adulterated with glucose syrup weight of 10%, 50%, 70% and 90%, and each sample was analysed. Pure honey at ambient temperatures exhibits peculiar non-Newtonian rheological behaviour. Adulteration with glucose syrup (a Newtonian fluid) drags its viscosity towards Newtonian flow behaviour. Malcolm Cross and Ostwald-de Waele Power-Law models were used to fit the rheological data, and the former fitted better than the latter. The behaviour indices in both models increased with increasing adulteration of honey with glucose syrup. Chromatographic characterizations of honey which provides an acceptable measure of honey quality corroborated the conclusions derived from the rheological characterization of this study.