60 QUEENSLAND AGRICULTURAL JOURNAL. [1 Jury, 1898. 
Vignerons should be prepared for the development in their wines of this 
disease in those seasons when drought, continued wet weather before the 
_ vintage, rotting of grapes, or fungus disease have been the cause of instability 
of the colouring matter and an abnormal secretion of oxydase. ‘The instability 
of the colouring matter can be considerably ameliorated by careful attention to 
the acidity of the must, correcting it by addition of tartaric acid where wanting, 
which will assist in fixing the colour. 
There are two ways of curing this disease: One is by pasteurisation, or 
heating the wine to 150 degrees, which kills the oxydase; but, as the 
apparatus to effect this is not to be found in Queensland, the second method 
must be adopted, and that is by exposing the oxydase to the influence of 
sulphurous acid, which also affects its action. 
The easiest way of doing so is to rack the wine into a clean eask in which 
has been burnt 1 to 2 oz. of sulphur in the form of a match to each 100 
gallons of wine, according to the severity of the case. It is essential that the 
remedy is not abused, or there will be a risk of bleaching the wine very | 
seriously. A far better way of administering the sulphurous acid is in the 
shape of bi-sulphite of potash, from 4 to 1 oz. for every 100 gallons, which 
should be dissolved in some wine and mixed with the rest during the racking ; 
give a light fining afterwards. By drawing off a little wine and exposing it 
for some hours to the air, it will be seen if enough sulphurous acid has been 
given ; if it continues to darken and cloud, more must be used. 
ACESCENCE. 
Acesence, or acetification, is a disease caused by a special germ which 
converts the alcohol of wine irto acetic acid; it generally follows the 
appearance of flowers, as the whitish scum is called, on the surface of wine 
due to a minute fungus called Uycoderma vini, so that vignerons should be 
careful to prevent the appearance of flowers by keeping the cask well filled, or 
if by accident they form on the surface of the wine get rid of them by filling 
up the cask sufficiently to reject them out of the bunghole. The flowers are 
not of so much danger to the wine in themselves, as being the forerunners of 
_ the germs of acetification, indicating by their presence a condition of affairs 
favourable for the development of the Mycoderma aceti. -An insufficiently 
filled cask is therefore one reason for acetification. 
Guyot, a French wine expert of earlier times, gives as another reason for 
acetification the law of assimilation as expounded by Ampére. He (Ampére) 
says :—‘ When a certain quantity of water contains in solution the elements 
of several crystallisable salts, if you introduce into this water a crystal composed 
of. one of those salts of which the water contains the elements, there will be 
formed in the vessel a quantity of analogous crystals of the same composition 
as that which has been introduced into the mother liquid, and no other erystal 
will be deposited,” giving, as examples of this law, the smallpox and other 
diseases besides many others drawn from the animal, vegetable, and mineral 
kingdoms. Guyot contends that under this law if at any given point of a 
cask the wine begins to acetify, such as at the bunghole, taphole, or a leakage 
through a stave, the law of assimilation will assert itself, and little by little 
the whole body of liquid will acetify ; the exterior point of acetification acting 
ye the mass of the wine as the single crystal of salt did to Ampére’s compound 
solution. 
Modern researches have proved that the transformation of alcohol into 
acetic acid is the work of a yeast or ferment, so that Guyot’s theory of 
acetification is inadmissible ; but at the same time vignerons would do well to 
suppress similar sources of infection, as, whether germs or the law of assimilation 
are the cause, the fact of the bulk of the wine being in contact with one or 
more points where acetification has started cannot but be injurious to it. 
Another reason for the presence of germs of acidity in wines is the system 
of bunging adopted by many vignerons in Queensland—a worse could hardly 
