Honey adulteration detection: voltammetric e-tongue versus official methods for physicochemical parameter determination

J Sci Food Agric. 2018 Aug;98(11):4304-4311. doi: 10.1002/jsfa.8956. Epub 2018 Mar 25.

Abstract

Background: The aim of this study was to evaluate the usefulness of a voltammetric e-tongue (three electrodes: reference electrode (Ag/AgCl), counter electrode (glassy carbon electrode rod) and working electrode (Au, Ag, Pt and glass electrode)) for honey adulteration detection. For this purpose, 55 samples of authentic honey (acacia, honeydew, sunflower, Tilia and polyfloral) and 150 adulterated ones were analyzed. The adulteration was made using fructose, glucose, inverted sugar, hydrolyzed inulin syrup and malt wort at different percentages: 5%, 10%, 20%, 30%, 40% and 50%, respectively. The e-tongue has been compared with the physicochemical parameters (pH, free acidity, electrical conductivity (EC) and CIEL*a*b* parameters (L*, a* and b*)) in order to achieve a suitable method for the classification of authentic and adulterated honeys.

Results: The e-tongue and physicochemical parameters reached a 97.50% correct classification of the authentic and adulterated honeys. In the case of the adulterated honey samples, the e-tongue achieved 83.33% correct classifications whereas the physicochemical parameters only achieved 73.33%.

Conclusion: The e-tongue is a fast, easy and accurate method for honey adulteration detection which can be used in situ by beekeepers and provide useful information on EC and free acidity. © 2018 Society of Chemical Industry.

Keywords: adulteration; e-tongue, LDA; honey; physicochemical parameters.

Publication types

  • Comparative Study

MeSH terms

  • Acids / analysis
  • Chemical Phenomena
  • Electrodes
  • Electronic Nose*
  • Food Contamination / analysis*
  • Fructose / analysis
  • Glucose / analysis
  • Honey / analysis*

Substances

  • Acids
  • Fructose
  • invert sugar
  • Glucose