Beverley
Beekeepers' Association
The
local Beekeeping Association for East Yorkshire
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Honey
When does nectar become honey?
Plants live by the moisture and the nutrients they collect
from the soil and from carbon dioxide absorb from the
atmosphere. Within the green parts of the plant an involved
process known as photosynthesis takes place. Chlorophyll,
present in the cells, uses light energy to convert carbon
dioxide and water into many complex building chemicals
including glucose and other more complex sugars.
Plants secrete nectar, which is a watery solution of
various sugars, from nectaries usually situated in the
flowers. The main sugars are sucrose, glucose (dextrose)
and fructose (laevulose) present in varying proportions and
concentrations depending on the species of plant, the soil,
and climatic conditions. Nectar also contains traces of
protein, salts, acids, enzymes, and aromatic substances. So
there is some justification in giving honey the "bottled
sunshine" tag.
Nectar is offered at specific times in a regular daily
cycle according to the species of the flower. Its secretion
is influenced by the weather, particularly temperature and
humidity, and also by soil moisture. Nectars vary
considerably in flavour and sweetness, plum nectar has a
sugar concentration of only 15%, lime 32-35%, white clover
40% and marjoram reaches 76%.
Having gathered some nectar, it is carried back to the hive
in the bee's honey sac, a non-digestive crop and passed on
to the house bees. Two things have to be done to convert
the nectar into honey. The sucrose in the nectar has to be
split by the addition of an enzyme (invertase) produced in
the glands of the bee, into two simple sugars fructose and
glucose. This allows high concentrations of sugar solutions
to be achieved. Secondly the water content, anything up to
80% has to be reduced to below 22% to prevent fermentation.
The house bees do this by exposing small quantities of the
liquid to the warmth (av. 33°C) of a well ventilated part
of the hive. The object of these changes is to produce a
food which when sealed over in the cells of the comb will
keep until needed, and is suitable with the addition of
water for feeding to larvae when rearing starts in the
spring. Strong colonies in good foraging areas can store
two to four times as much honey as they need for winter
survival; it is this surplus that the beekeeper can take.
A
Word about Rape Honey
Oil-seed
rape yields very large quantities of honey with a high
glucose content which causes it to granulate very quickly
if left in the supers too long. The crop must be removed
just as soon as it has been capped and extracted straight
away. Alternatively rape honey can be allowed to set in the
supers. The whole lot can then be cut out, mashed and
heated to redissolve the crystallized honey before
screening away from the wax.
A
Word about Borage Honey
Borage
also gives very high honey yields with high fructose
content so it will not granulate easily. Care must be taken
to ensure that only fully `capped' honey is extracted. This
honey will ferment easily if it is not fully ripe.
A
Word about Heather Honey
Heather
honey is peculiar in that it is thixotropic as a result of
high protein content. It produces a viscous gel unless
sheared (stirred) and the combs cannot be extracted using a
centrifugal extractor. It must either be extracted in a
heather press or using specialized equipment. It can
however be sold as ‘cut comb’ honey.