Analysis of polyphenolic components of Hungarian acacia (Robinia pseudoacacia) honey; method development, statistical evaluation

Abstract

Acacia honey is a popular and high-value type of monofloral honey, which is considered a Hungaricum. Pollen analysis is the primary testing method to determine the botanical origin of honey, but in recent years polyphenol analysis has been frequently used as a complementary method for its identification. In this paper, a newly developed UHPLC-ESI-MS/MS method is presented to investigate the polyphenol composition of fifty-three Hungarian acacia honey. Based on our study the 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, ferulic acid and chrysin were the most abundant polyphenol components in the tested honeys. PCA analysis of the polyphenol data revealed that the variance of the polyphenol components is primarily determined by caffeic acid (52%), secondarily by 4-hydroxybenzoic acid (36%) and thirdly by p-coumaric acid (11%). Pollen analysis of the samples revealed that besides acacia pollen, rape pollen, rose pollen and phacelia pollen was present in 93%, 88% and 70% of samples respectively. Different classification models were used to find the correlation between the pollen composition and the polyphenol pattern. The best classification accuracy of 78.4% was achieved using the coarse tree model.