Quality authentication and geographical origin classification of honey of Amhara region, Ethiopia based on physicochemical parameters

Abstract

The knowledge of the physicochemical properties of honey from different botanical and geographical origins is important to identify the honey with better quality. Accordingly, the Amhara region of Ethiopia is producing honey of different quality for the local and export market. Thus, the study was aimed at estimating the quality and developing a chemometric model for geographical origin classification of the region’s honey based on its physicochemical parameters. A total of 47 honey samples were collected from 7 administrative zones (East Gojjam, West Gojjam, Awi, South Gondar, South Wollo, North Wollo and Wag Himera zones) of three major provinces (Gojjam, Gondar and Wollo) of the region. Eight physicochemical parameters of the honey samples were determined using internationally accepted standard methods. In view of that, the average values of the studied physicochemical parameters at each administrative zone were in the range of 16.06–18.51, 0.26–0.60, 61.45–71.41 and 2.96–4.73 g/100 g of honey for moisture content, ash content, total reducing sugar and apparent sucrose content respectively. In addition, pH (3.85–4.23), free acidity (26.39–37.80 meq/kg), electrical conductivity (33.37–63.43 μS/cm) and HMF (3.88–8.50 mg/kg) were determined in the studied samples. Based on these values the region’s honey was in a good quality that meets the national and international standard limits. In the PCA model, the first three principal components explained about 69.14% of the total variations and the LDA model had an average of 80.85% discrimination power. The LDA model was checked by cross-validation method and 100% of samples in the validation set were correctly classified by the model.