Effect of high humidity in the beehive on the water content of honey

test specimens

A balance is established between the water content of the honey and the surrounding air humidity. The balancing moisture content of honey at a relative humidity of 55% is about 17.5%. At a relative humidity of 80%, honey has a water content of over 30% (source: The hygroscopic properties of different dilutions of Honey, Doull & Mew 1977).

The wax capping of the honey cells slows down the speed of these water transports, but does not prevent diffusion. The wax layer is so thin that the resistance of this cap to water vapour diffusion is just as high as that of a 3.3 cm thick layer of air. The experimental setup for determining the diffusion density is explained below. Continue reading “Effect of high humidity in the beehive on the water content of honey”

Thermal insulation of honeycombs

When considering the thermal insulation of bee hives, we also have to consider the honeycomb construction with its air layers in between. These layers themselves act as thermal insulation. The more honeycombs between the bee cluster and the side wall, the higher the insulation. I.e. with regard to the side thermal insulation, the broad constructions of the modern hives are quite helpful. Continue reading “Thermal insulation of honeycombs”

Straw bee hive with frames

apiary of the abbey beekeeping

Almost 100 years ago, straw hives with frames were already used for beekeeping. The hive has a wooden bottom, the entrance hole is only a small slit, the side walls are made of straw and the lid is a double-walled wooden construction with straw filling. In these hives there were no problems with mould and condensation, although the lid construction is not highly vapour permeable. The construction demonstrates that humidity can also be carried away through the side walls by diffusion. Further information under Diffusion and D-cover.

 

Physical properties of propolis

Wood with propolis layer

The antiseptic function of propolis is generally known. This property slows down the development and spread of pathogenic germs in hives and tree hollows. However, propolis also fights condensation and mold in a different way, which is probably unknown to beekeepers. It is a simple physical effect: In the propolis layer there is no capillary condensation, propolis is not hygroscopic. Continue reading “Physical properties of propolis”

News on the diffusion lid, September 2017

diffusion lid

Unfortunately, sheep’s wool in the form of insulation mats is usually treated with moth repellents. Please do not use this for the Diffusion lid! It is also best to buy untreated sheep’s wool directly from the shepherd or farm. Hemp insulation wool is also permeable and can be used as an alternative. The insulation properties are, however, slightly worse. Continue reading “News on the diffusion lid, September 2017”

Water formation by the metabolism of the bees

In our calculations we have only considered the water contained in the honey so far (200ml water per Kg Honey). This is a customary assumption, but that’s only a part of the truth.

The water formation caused by the metabolism of the bees is much bigger.
Oxidative water is produced during the aerobic metabolism of honey (glycolysis or dissimilation)C6H12O6 + 6 O2 -> 6 CO2 + 6 H2O
(glucose + oxygen -> carbon dioxide and water)In this case 600 ml of oxidation water are produced per kilo of glycose or fructose. This means that another 4.8 liters of water are produced per 10Kg Honey. 6,8 liters of water are produced by the metabolism of 10 kg of honey at all.