Foods: Their Composition and Analysis A Manual for the Use of Analytical Chemists
November 11, 2008 by admin
ABSINTHE
Absinthe is a yellowish green liqueur which contains as a peculiar and distinctive ingredient a poisonous oil having a deleterious action on the nervous system This wormwood oil is the produce of the Artemisia absinthium Other flavouring oils are always present such as peppermint angelica cloves cinnamon and aniseed The green colour is produced by the juice of spinach nettles or parsley or in other words it is due to chlorophyll The absorption spectrum of properly made absinthe is the same as that of chlorophyll Most samples of absinthe contain sugar The average composition of the liqueur as consumed in London where its use is on the increase is as follows Per cent
Absolute alcohol 50 00
Oil of wormwood 33
Other essential oils 2 5 2
Sugar 1 50
Chlorophyll traces
Water 45 65
On diluting absinthe the essential oils are thrown out of solution and the liquid becomes turbid The reaction is always slightly acid due to a trace of acetic acid Adulterations of A bsintlie The composition of absinthe appears to be fixed by no definite standard of strength therefore practically the analyst has to look only for such substances is injurious colouring matters and metallic impurities Sulphate of indigo with turmeric is not infrequently employed as a colouring agent and similarly picric acid has been detected and salts of copper The latter is readily discovered by diluting the liqueur and adding ferrocyanide of potassium which if copper be present will give a brown colouration picric acid and indigo are detected in the way elsewhere described.
Analysis of Absinthe The alcohol may be determined by distillation after diluting the liqueur to cause the oils to separate and getting rid of some portion by filtration To make an estimation of the essential oils a measured quantity of the liqueur is diluted to twice its volume by the addition of water carbon disulphide is added and the mixture shaken up in the tube described at p 69 The carbon disulphide dissolves all the essential oils and on evaporation leaves them in a state pure enough to admit of their being weighed Absinthe when taken habitually and for a lengthened time produces a peculiar train of nervous symptoms which the French physicians affect to distinguish from the similar symptoms produced in inebriates by alcohol In epilepsy caused by indulgence in absinthe M Voisin states as the results of clinical observation that the number of fits is far gi eater than in alcoholic epilepsy
Foods: Their Composition and Analysis A Manual for the Use of Analytical Chemists and Others. With an Introductory Essay on the History of Adulteration By Alexander Wynter Blyth
