THE USE OF PURE YEASTS IN WINE MAKING. 



29 



taken and might mislead. Therefore these discrepancies are impor- 

 tant, as observations made under these circumstances might readily 

 lead to error if one is dependent wholly upon spindle readings. 



Burring these evident inaccuracies, resulting from conditions which 

 the observer could neither remedy nor control, the table brings 

 together the salient facts of the duration and progress of the fermen- 

 tation. The Brix readings can be depended upon to show the 

 attenuation after the vats came into full fermentation. 



All of the yeasted vats show a marked uniformity of behavior as 

 to rise of temperature and the attenuation of the must so as to bring 

 it into condition for drawing off in a given number of hours. An 

 even progress on the unyeasted vats is also shown, but the attenua- 

 tion is much slower, and, though these vats were actually drawn after 

 about twenty-four hours' longer period on the pulp than the yeasted 

 . two <.f them \\.-re plainly not ready to draw, and foamed so 

 much on the press that they were handled with difficulty. 



The >um <>f the observed temperatures of the respective vats, or 

 in other word-, the total increment of temperature, is interesting. 

 While these observations are not sufficiently accurate as to periods of 

 duration, etc., to warrant the development of a critical argument, 

 they do have a comparative value. The unyeasted vats, for the total 

 time they stood, show u temperature increment in excess of the 

 others, and if they had been carried to the same attenuation as the 



would liuve been more noticeable still. It is 



true that none of the unyeasted vats reached an elevation of tem- 

 perature within 5 of the yeasted ones, yet if they had completed 

 the tumultuous fermentation they would surely have equaled the 

 other> in the decree of heat developed. The highest temperatures 

 noted in this \\mery were produced in vats undergoing natural 

 fermentation. 



TABLE I. Comparison of temperature and Brix readings on yeasted and unyeasted vats. 



