Spanish researchers have carried out a preliminary study using an electronic tongue based on potential multistep pulse voltammetry, in combination with multivariate statistical techniques to detect and quantify sugar syrup in honey. Pure monofloral honey (heather, orange blossom and sunflower), sugar syrup (derived from rice, barley and maize), and samples simulating adulterated honey with different percentages of syrup (2.5, 5, 10, 20 and 40) were evaluated. An automatic, electrochemical system for cleaning and polishing the electronic tongue sensors (Ir, Rh, Pt, Au) significantly improved the repeatability and accuracy of the measurements. PCA analysis showed that the proposed methodology is able to distinguish between types of pure honey and syrup, and their different levels of adulterants. A subsequent PLS analysis successfully predicted the level of the adulterants in each honey, achieving good correlations considering the adjusting parameters. The measurement system here proposed has the potential to be a quick and effective option for the honey packaging sector. However, much further work is needed to see how effective this technique is with a wider range of monofloral honey, blended honey and commercial sugar syrups.
Read the abstract at: electronic tongue and honey adulteration