Enzyme activity, amino acid profiles and hydroxymethylfurfural content in Ethiopian monofloral honey

The enzymes activity, hydroxymethylfurfural (HMF) and amino acids in honeys are relatively low. However, they play very significant role for honey quality. In this study, enzymes, amino acids and HMF contents of Ethiopian monofloral honeys were investigated. Diastase, invertase and HMF were analyzed based on the Harmonized International Honey Commission method and amino acids using amino acids analyzer (HPLC). Diastase activity ranged from 3.91 +/- 0.730 (Schefflera abyssinica) to 13.6 +/- 2.30 [Becium grandiflorum (L: Lalibella)]; invertase 36.5 +/- 1.93 (Leucas abyssinica) to 4.85 +/- 2.36 (Schefflera abyssinica); and HMF 0 +/- 0 (Hypoestes and Leucas abyssinica) to 3.37 +/- 1.73 (Croton macrostachyus). Significant variations were observed among Schefflera abyssinica honeys in diastase content, despite being from the same botanical origin. Significant variations were also observed among Becium grandiflorum honeys in invertase and diastase contents. Bees' geographical race and location affected enzymes activities. Lower level of enzymes could be an intrinsic characteristic of Ethiopian honey. Thus, enzymes activity alone cannot be a worthwhile indicator of quality for Ethiopian honey; besides diastase and invertase activity, the quality control of Ethiopian honeys should be supported by HMF parameters.