830 Experiments 



So under the influence of oxygen at high tension, the mycoderm 

 which consumes the alcohol entirely and the one which merely 

 transforms it into acetic acid are absolutely killed. The wine thus 

 retains its alcohol and its acid content (Exp. CCCCXLV) . 



The effect of the oxygen begins to appear before the tension 

 which corresponds to 5 atmospheres of air (Exp. CCCCXLIV.) 



However the wine undergoes certain alterations. The coloring 

 matter is precipitated in the form of films adhering to the vessel, 

 it "fades" more or less completely, and sometimes has a beautiful, 

 slightly amber color (Exp. CCCCXLV) , sometimes a tint like 

 Rancio wine (Exp. CCCCXLVIII) or finally an almost entire loss 

 of color (Exp. CCCCXLIX). 



In taste, the wine appears to age rapidly (Exp. CCCCXLVI) ; it 

 even becomes quite bitter (Exp. CCCCXLV) or very much weak- 

 ened (Exp. CCCCXLVI) . It loses its bouquet, and sometimes has 

 a slightly cooked flavor (Exp. CCCCXLVIII) . 



In a word, the wine appears to undergo the alterations produced 

 by excessive heating, brought on by contact with the air. 



I will call attention to the fact that in all these experiments 

 the pressure was extremely high, carried no doubt far beyond 

 what would be needed to kill the germs. A weaker pressure per- 

 haps would not change the wine, and yet would preserve it from 

 harmful fermentations. Perhaps it would even be slightly im- 

 proved, as happens in the case of harsh and raw wines when they 

 are heated in accordance with the rules established by M. Pasteur. 



Besides, the wines were tasted after a fairly long time. Possibly 

 if they had been tasted immediately, a certain improvement would 

 have been noted. 



All these questions, moderately interesting from the scientific 

 point of view, take on a considerable importance when considered 

 from another point of view. However, I could not turn aside unduly 

 from my general studies to investigate them, and after noting the 

 preceding facts, I had to postpone until another time detailed re- 

 searches and practical applications, if possibly there are any. 



I merely report here an experiment which proves that the limit 

 at which oxygen at high tension acts unfavorably on wine is quite 

 low; hence we conclude that its favorable concentration, if there 

 is one, as the preceding experiments seem to indicate, might be ob- 

 tained industrially, since ordinary air could be used. 



Experiment CCCCLII. July 15. Good red wine in two sealed bottles 

 the corks of which are pierced by a hole. 

 A, in the air, upright, 



