THE MICROSCOPE. 



KEBR.TJARY, 1896. 



Number 38. New Series. 



The Spoiling of Fermented Drinks. 



BY A. DEROS. 

 Translated from Le Micrographe Preparateur. 



The Blue Ixfectiox. — This alteration, althougli very 

 rare in red wines, is quite common in the white wines, 

 since the grape vines have become infested with many 

 different species of mushrooms. The flat wines, contain- 

 ing little acid or alcohol, are most susceptilde to this 

 change, especially if they are rich iu nitrogenous substan- 

 ces. Wines which should be clear when drawn, then 

 become muddy and of a liluish color when looketi 

 through. 31. Robinet attributes this change to the 

 presence of mycodermes liaving a strong resemblance to 

 mycoderma aceti. With a high power of magnification 

 the presence of grayish mycoderraes, which multiply by 

 budding, can be distinguished in these blue wines. 



To counteract this blueness, add to the wine a quan- 

 tity of alcohol sufiicient to bring it up to 12 degrees: the 

 acidity can also be brought back to live grammes by the 

 addition of citric acid. If the disease resists this, it will 

 be necessary to add six or eight grammes of tannin to 

 the hectolitre and afterwards make a strong collage. 



The Greasy Ixfectiox. — White wines, champagne in 

 particular, sometimes become sticky, slimy, stringy, and 

 quite unfit to drink. This change takes place not onlv 

 in wines in casks but also in bottled wines which are 

 properly corked and cared for. It is the grease. 



There is produced in the wine a particularly sticky 

 substance, which has been called gluten, gliadin, glaia- 



