HONEY 523 



The nectar secreted by the nectaries of numerous flowers con- 

 tains as its principal constituent cane-sugar (sucrose). This nectar 

 is sucked up by the bee through an air-tight tube formed from its 

 ligula and labial palps. It is carried through the oesophagus into 

 the crop or honey-sac, becoming mixed on its way with the salivary 

 secretion from special glands. During its stay in the honey-sac, 

 the sucrose of the nectar is converted into invert-sugar (dextrose 

 and levulose) by the enzyme, invertase, which is contained in the 

 salivary secretion. Arrived in the hive, the bee empties the honey- 

 sac by regurgitation into a cell of the honeycomb. From the cells 

 of the honeycomb the honey is separated by cutting and draining, 

 or by centrifugation, or by pressure with or without heat. 



Some quantity of honey is produced in England, but the chief 

 sources of supply are California, Chili, and Jamaica. 



Description. Honey, when fresh, is a viscous, transparent liquid, 

 becoming semi-solid on standing from crystallisation of the dextrose 

 contained in it. It varies in colour from nearly white to reddish 

 brown. It has an agreeable odour and a sweet, slightly acrid taste, 

 both odour and flavour being to a great extent dependent upon the 

 nature of the flowers from which the nectar was collected. 



Constituents. Pure honey consists chiefly of dextrose and levulose 

 together with water in which these are at first dissolved. It also 

 contains small quantities of volatile oil, formic acid, sucrose, dextrin, 

 proteids, wax, pollen grains, and often fragments of dead insects, 

 &c. It yields from 0*3 to (V8 per cent, of ash containing traces only 

 of sulphate and chlorides, and usually exhibits slight dextro- or 

 laevorotation (+ 3 to 3). 



Uses. Honey is largely used as a demulcent and sweetening agent 

 af well as for its nutritive properties. 



Varieties. Honey obtained from heather and clover is considered 

 to have the finest flavour, while that from Coniferous plants and 

 species of Eucalyptus is the least agreeable. Some indication of 

 the source of the honey may be obtained from the identity of 

 the pollen grains contained in it. Jamaica honey is often dark in 

 colour, while Australian honey usually has an unpleasant eucalyptus 

 flavour. 



Adulterants. The most common adulterants are sucrose and 

 commercial glucose both of which produce dextrorotation in the 

 honey. The presence of calcium sulphate, which may be tested for 

 in the usual way either in the honey or in the ash, indicates com- 

 mercial glucose. Pure honey should show at most a slight turbidity 

 when mixed with three or four volumes of alcohol (absence of dextrin, 

 a frequent constituent of commercial glucose). 



