Comparing the physiochemical properties of natural, synthetic and adulterated honeys

Abstract

Background: The fraudulent practice of selling adulterated honey is wide spreading because of strong economic incentives. Therefore, the objective of this study was to compare the physiochemical properties of natural and synthetic honeys. Methods: Tualang honey was used as natural honey, and the synthetic honey was prepared in the laboratory, whereas a few market-purchased honeys was used for comparison. The tested properties included pH, colour, electrical conductivity, viscosity, moisture, total soluble solid, antioxidant capacity and hydroxymethylfurfural content which are considered as rapid tests and no advanced analytical tool is required. Results: Of the tested parameters, electrical conductivity and rheology seemed to be more significant for detecting honey adulteration. Adulteration with sugary substances could change the flow behavior of honeys. The significant difference could be seen from the viscosity profile of honeys at different shear rate after diluted to 50% w/v. Somehow, the antioxidant capacity which was expressed as radical scavenging activity and ferric reducing power was unable to detect adulteration in honey. This was because the high content of HMF in adulterated honeys also contributed to high antioxidant capacity. Conclusions: The results indicated that no single method could differentiate natural and adulterated honey, the combination of the selected parameters, specifically conductivity, rheology and HMF was able to conform the quality of honey on the aspect of adulteration.