Der Anteil an Honigtau und die elektrische Leitfähigkeit des HonigsH. Pechhacker
Höhere Bundeslehr- und Versuchsanstalt für Wein- und Obstbau mit Institut für Bienenkunde, Abteilung Bienenzüchtung, A-3293 Lunz am See, Österreich
Abstract - Honeydew content and electrical conductivity of honey
During the honey flow from honeydew in Lunz am See, Austria, between June 30th and July 21 st 1987, samples of returning fieldbees from 3 specially prepared colonies (without any reserve of honey and pollen) were collected daily at various times. The bee samples were killed in liquid nitrogen and stored at -18°C. At the end of the experiment honey samples were also taken from each comb of the colonies. The following data were collected from the bees: weight of the honeysac, sugar content in the honeysac (Anthron method = total sugar analysis) and the botanical origin of the honeysac content (on the basis of pollen grains and fungus spores). Measurements of the honey samples were as follows : electrical conductivity, number of pollen grains (nectar plants and nectarless plants) and honeydew components (fungus spores) in the honey sediment per mg sugar. Significant correlations were found between electric conductivity and sugar content originating from honeydew and number of honeydew components per mg sugar in the honey (fig 1 A, B). Significant negative correlations were also found between the percentage of honeydew sugar in the honey and the number of honeydew components in the honey sediment per mg sugar, the number of pollen grains from wind-pollinating plants per mg sugar and the relation of pollen grains of nectar plants to pollen of nectarless plants per mg sugar (fig 2A, B, C). The result of higher honeydew content in the honey is a significant higher electric conductivity, a lower relation between the number of pollen grains from nectarplants to pollen of nectarless plants per mg sugar and a general lower content of sediment components per mg sugar in the honey.
Key words: honey / electrical conductivity / honeydew / honeydew component / pollen content