EXTRACTABLE ORGANIC-SUBSTANCES FROM NEW-ZEALAND UNIFLORAL MANUKA (LEPTOSPERMUM-SCOPARIUM) HONEYS

The range and concentrations of extractable organic substances occurri ng in 14 samples of New Zealand manuka (Leptospermum scoparium) honey taken in the 1989-1990 season were compared with those found in some 1 985-1987 samples. The samples were analysed using gas chromatography w ith flame ion detection and combined gas chromatography-mass spectrome try. The concentrations of 69 compounds are listed. The results verify an earlier proposition that irrespective of season and geographical o rigin, samples of unifloral manuka honey are characterized by a combin ed concentration of 2-hydroxy-3-phenylpropionic acid and 2-hydroxy-3-( 4'-methoxyphenyl) propionic acid greater than 700 mg/kg honey, a combi ned concentration of syringic acid and 3,4,5-trimethoxybenzoic acid gr eater than 35 mg/kg honey, and a combined concentration of acetophenon e and 2-methoxyacetophenone greater than 20 mg/kg honey.