Correlation between physical and chemical properties of honey samples from Malaysia

Abstract

This study was focused on the establishment of statistical correlation between physical and chemical properties of honey samples, namely Tualang, Gelam and Acacia honey from Malaysia. The physical properties studied were pH, colour, moisture, ash, electrical conductivity, total soluble solid (TSS) and acidity. The chemical properties evaluated were hydroxymethylfurfural (HMF), total phenolics (TPC), total flavonoids (TFC) and mineral content, as well as radical scavenging activity. The methods used for the physical properties were based on Official Method of Analysis (AOAC), while the chemical composition of honey was determined using mass spectrometric and spectrophotometric methods. The results showed that the physical and chemical properties of honey samples were positively correlated (r>0.700) by using Pearson’s correlation coefficient. From dendrogram, three major groups were clustered based on the cluster distance between parameters of honey. The colour and TSS exhibited the longest cluster distance than the other parameters. Therefore, both parameters were used as a rapid physical indicator to estimate the concentration of HMF, mineral content, TPC and TFC with the confident level 95%. The presence of apigenin, luteolin, caffeic acid and p-coumaric acid was believed to contribute to the dark coloured honey, besides HMF. The TSS was contributed by the chemical compounds such as polyphenols and mineral content. The finding was also supported by the high percentage of the total variance in the first principal component (PC1=97.8%) of multivariate analysis. As a conclusion, the relationship between physical and chemical properties of honey has been established based on the available samples. The relationship showed that for honey with colour less than 80.00 mm Pfund scale, the TPC and TFC value can be less than 42.92 mgGAE/100g and 7.54 mgRE/100g, respectively. For TSS, a value of around 74 % will contribute to about 1700 mg/kg of total mineral content