Unusually Severe Granulation of Winter Stores Caused by Nectar from Ivy,Hedera Helix, in Ireland

Abstract

SummaryIn honey that had granulated in combs in winter to such an extent that it appeared to be almost dry powdered sugar, most of the pollen was from ivy, but no melezitose was present, although honeydew produced by Aphis hederae on ivy did contain melezitose. Although such extreme granulation is often caused by melezitose in honeydew, the cause in this case was the exceptionally high proportion of glucose that ivy nectar contains. The overall water content of the excessively granulated honey was unusually low, presumably because of the high equilibrium vapour pressure of honey rich in glucose and evaporation of water from the relatively dilute liquid phase left by the extreme granulation.