How Do Bees Make Honey?
We, as beekeepers, are interested in how much honey our bees are collecting, both for themselves and for us, if there is any surplus.
Most honey comes from nectar produced by plants. There is also honeydew from the secretions of aphids although this has come indirectly from plants. Nectar is produced by the nectaries of plants. These are usually found as part of the flowers but some plants have nectaries in funny places. For example field beans and bracken have extra floral (outside the flower) nectaries.
Nectar attracts insects to flowers and as the insect collects the nectar it “accidentally” moves pollen from one flower to another and pollination occurs.
Nectar is basically a solution of sugars in water. Other ingredients are present in small quantities and include minerals, organic acids, vitamins, pigments, aromatic substances and amino acids. The percentage of sugar varies from 5 to 80% but an average nectar has around 20% sugar. The main types of sugar in nectar are fructose, glucose and sucrose. Not many nectars have sucrose (the same sugar you put in your tea) as the dominant sugar. A high sucrose content is one way Trading Standards check for the adulteration of honey with sugar. Some nectars have equal sucrose, fructose and glucose. Another group has either glucose or fructose as the dominant sugar with very little sucrose.
On locating nectar the worker bee extends its proboscis from its resting position. The liquid is sucked up and passes through the pharynx and oesophagus into the honey sac. The honey sac is not a digestive organ but acts as a collecting chamber. The capacity of the honey sac is about 50-60 ul.(microlitres)
Processing the honey consists of removing water to less than 20%. Also chemical changes to the sugars which are brought about by enzymes. These are produced by the hypopharyngeal glands (found in the head). Secretions from the salivary glands in the head and thorax, also contain enzymes.
The forager will repeatedly regurgitate and swallow the nectar on the way back to the hive. When the bee returns to the hive she regurgitates the nectar and it appears as a droplet at the base of the glossa this is then sucked up by a house bee. The house bees continue to process the nectar by continually regurgitating and swallowing the nectar and adding enzymes in the process. The nectar is further dehydrated by the regurgitation process. Enzymes are added which break down the sucrose to the simple sugars, glucose and fructose. This enzyme is sucrase also known as invertase.
Droplets of “honey” are placed in the cells “hung up to dry” or the honey is smeared over the walls of the cells to aid evaporation of water. Fanning of the bees creates a flow of air over the honey to hasten evaporation of the excess water. When the honey has got down to less than 20% and the cells are full, then the cells capped with wax. Occasionally, if there is a very heavy flow of nectar then the bees may fill and cap the cells before it is properly ripe.
How quickly honey granulates is related to the ratio of glucose and fructose in the honey. Honey where glucose predominates granulates faster than honey where fructose predominates. All honey will granulate eventually as it is a supersaturated solution. Honey from oil seed rape is very well known for its rapid granulation. This can occur while the honey is still on the hive.
Ref: Crane, Eva, Honey A Comprehensive Survey
Most honey comes from nectar produced by plants. There is also honeydew from the secretions of aphids although this has come indirectly from plants. Nectar is produced by the nectaries of plants. These are usually found as part of the flowers but some plants have nectaries in funny places. For example field beans and bracken have extra floral (outside the flower) nectaries.
Nectar attracts insects to flowers and as the insect collects the nectar it “accidentally” moves pollen from one flower to another and pollination occurs.
Nectar is basically a solution of sugars in water. Other ingredients are present in small quantities and include minerals, organic acids, vitamins, pigments, aromatic substances and amino acids. The percentage of sugar varies from 5 to 80% but an average nectar has around 20% sugar. The main types of sugar in nectar are fructose, glucose and sucrose. Not many nectars have sucrose (the same sugar you put in your tea) as the dominant sugar. A high sucrose content is one way Trading Standards check for the adulteration of honey with sugar. Some nectars have equal sucrose, fructose and glucose. Another group has either glucose or fructose as the dominant sugar with very little sucrose.
On locating nectar the worker bee extends its proboscis from its resting position. The liquid is sucked up and passes through the pharynx and oesophagus into the honey sac. The honey sac is not a digestive organ but acts as a collecting chamber. The capacity of the honey sac is about 50-60 ul.(microlitres)
Processing the honey consists of removing water to less than 20%. Also chemical changes to the sugars which are brought about by enzymes. These are produced by the hypopharyngeal glands (found in the head). Secretions from the salivary glands in the head and thorax, also contain enzymes.
The forager will repeatedly regurgitate and swallow the nectar on the way back to the hive. When the bee returns to the hive she regurgitates the nectar and it appears as a droplet at the base of the glossa this is then sucked up by a house bee. The house bees continue to process the nectar by continually regurgitating and swallowing the nectar and adding enzymes in the process. The nectar is further dehydrated by the regurgitation process. Enzymes are added which break down the sucrose to the simple sugars, glucose and fructose. This enzyme is sucrase also known as invertase.
Droplets of “honey” are placed in the cells “hung up to dry” or the honey is smeared over the walls of the cells to aid evaporation of water. Fanning of the bees creates a flow of air over the honey to hasten evaporation of the excess water. When the honey has got down to less than 20% and the cells are full, then the cells capped with wax. Occasionally, if there is a very heavy flow of nectar then the bees may fill and cap the cells before it is properly ripe.
How quickly honey granulates is related to the ratio of glucose and fructose in the honey. Honey where glucose predominates granulates faster than honey where fructose predominates. All honey will granulate eventually as it is a supersaturated solution. Honey from oil seed rape is very well known for its rapid granulation. This can occur while the honey is still on the hive.
Ref: Crane, Eva, Honey A Comprehensive Survey