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The taste and chemical constituents of the wine are not very 
perceptibly altered, but the wines become unsightly. When looked 
at through clear glass, either the white or red wine shows a seud, 
and from brilliant and limped when fresh drawn from the cask it 
becomes dull, shows an irridescence on the surface, and the colour- 
ing matter gradually oxidising throws a brown-coloured sediment. 
The wine sometimes has a leathery smell, and has a slightly acidu- 
late and bitterish taste. 
The oxidising diastase feeding on the albuminoid substances in 
the wine is more commonly met with in wines produced from grapes 
grown on rich alluvial soils. Tannin, which coagulates albumen, is 
generally deficient in such wines, and a slight addition of this sub- 
stance is often attended with good results. Sulphur, however, is in 
every case beneficial, and may be used at the rate of 6 to 30 
grammes of sulphurous acid per 100 gallons, or its equivalent, three 
to 15 grammes, of sulphur (Yoz. to Yoz.) or 12 to 60 grammes 
(4402. to 2ozs.) of bisulphite of potash. 
Amongst the diseases caused by anaerobic microbes— 
Mannitic Fermentation is one of the most troublesome in hot 
climates. The disease is caused by short, motionless, rod-like 
microbes, which congregate in groups and are often found asso- 
ciated with germs of other diseases. Two requirements are neces- 
sary for their development—the presence of unfermented sugar in 
the wine, and a higher temperature than is suitable for the yeast 
ferment, viz., 35°-40° C. (95°-104° F.). The disease generally starts 
in the fermenting vat whenever the temperature is allowed to go 
up too high. 
As a result of the presence of this microbe in large numbers, 
the unfermented sugar is transformed into another kind of sugar, 
called mannite, and into lactic acid, the result being a sour-sweet 
wine. 
The remedies are low temperature fermentation, or early for- 
tification with spirits of wine, or pasteurisation. 
The cream of tartar is not decomposed in mannitic wine, as is 
the ease in wines affected with the tourne disease. 
Tourne (Turning) and “Pousse” (Pushing) Diseases.—These 
diseases attack any kind of wine of low alcoholic strength. In 
appearance they are very much alike, and show like very minute 
filaments, grouped together in mucous bundles. 
The pousse microbes attack the tartaric acid of the wine, which 
it transforms into acetic and propionic acids, whilst in the Tourne 
the tartaric acid is turned into carbonic and lactic acids. The 
diseased wine tastes flat, its colour is precipitated. In the Pousse 
gases are generated, which, should the cask be tightly bunged, may 
