Gas Chromatographic Analysis of Free and Protein Amino Acids in Some Unifloral Honeys

Abstract

SummaryProline was the most important free amino acid, with phenylalanine next; it occurs in very high percentages in some honeys. Aspartic acid, glutamic acid and leucine were the most representative protein amino acids.The honeys analysed (24 from nectar, 4 from honeydew) differed in their total amino acid content, in the ratio between the amounts of free and of protein amino acids, and in the proportions of the various amino acids in the two fractions. Many factors contribute to the amino acid spectrum of a honey sample, and this spectrum cannot be used to characterize honeys, unless many elements of differentiation are available. Among the honeys studied, only those from Erica multiflora and Salvia pratensis could be considered typical of the plant source, in that they showed marked characteristics also shown by the nectar.Results do not allow any simple evaluation of the contributions of the honeybee and of the plant; one can only say that some nectars and honeydews have a typical amino acid spectrum, and that this persists in the honey, in spite of the levelling action of the honeybee.