Impedimetric sensing of honey adulterated with high fructose corn syrup

Abstract

Honey adulteration is a highlighted global issue in the modern food supply chain, the most commonly seen case is to cut honey with cheap and easily available sugar-based sweeteners, such as high fructose corn syrup (HFCS). To acquire a precise impedimetric response from such a high resistance sample, a low cell constant (13.9 cm−1) electrochemical chamber composed of two identical bare gold electrodes was developed for investigating the impedimetric differences among pure honey, blended honey, and HFCS. Charge transfer resistance (RCT) and logarithmic impedance (Log Z, in a broad frequency range of 101–105 Hz) were useful to discriminate all pure honeys from blended honeys with good resolution and reproducibility (relative standard deviations of RCT and Log Z were both less than 3% in triplicate tests). The data acquisition time for obtaining RCT and Log Z were only 3 min and 4 s, respectively, which means the proposed sensing approach is suitable for routine rapid screening purpose.