412 A^■Jl)lT^ OK wixi;. 



The fermentations here were fairly complete. The volatile 

 acidity was much less (some 25 per cent.) than in Table 1. The 

 same yeasts which gave the lowest volatile acidities in Table I. 

 namely JJM 2, and JjM 5. were also the lowest in this experi- 

 ment. 



C. H.vpcriiiiriits with Dc-siilphitcd Musi of 24.7' Balling. — 

 A must which for nearl\' a year had been kept from fermenting 

 by adding a lar<ie ([uantity of potassium meta-bisulphite was 

 heated on a water-bath to expel the sulphur dioxide. Whe-it 

 nearly all was driven oft" the must was brought to 24.7'' Ballii-.g 

 by adding water. The Ixittles were hlled, closed, and sterilized 

 as before. They were inoculated on December 18th, igiC). with 

 the same yeasts as in lA, with the addition of HaC^^. The tem- 

 perature was that of the room (20-26° C), and the fermenta- 

 tion was rather irregular. On the 16th January, J 917, the fer- 

 mentation was over, and the analytical determinations were 

 made. The original volatile acidit\- of the must used was 0.51 

 per mille. and the free and combined S( )^ were res])ecti\ely 13 

 and 127 mg. i)er litre. 



Tabic HI. 



GFT JjM Jl.\l JJ.\i .ij.M 



I [256 



Loss in neigiil. in i>r 21 21 26 32 20 



Alcohol, in wine, as volnnu- ])cr 



cent 71''^ 7-1''^ ■'^■.^1 ')-74 7-5" 



Volatile acid, as ,ur. acetic acid. 



per litre i .92 1 .93 1 .66 1 . 5(1 \ .98 



PJj (ireeii. (irecn. (irc-en. II;A 



I I -' .^ ?> 



Loss in weight, in gr. 28 .36 ,^ 1 27 2X 



Alcohol, in wine, as volume per 



cent .S.N I 10.70 10.09 9-'.^ N.56 



Volatile acid, as gr. acetic acid. 



I)er litre i .97 1.71 1 .67 i .76 i .64 



Again, in this case the same two yeasts. JJM 2 antl JJM 5. 

 as in Tables I and II, gave the lowest volatile acid, if we except 

 the new yeast IlaC... The relative positions occupied bv these 

 yeasts with regard to the volatile acid formed in all three ex])eri- 

 ments are very .similar, .so that they give the same general im- 

 pression. It was expected that the small amount of sulj^hurou.- 

 acid would exert a hindering eft'ect on the alcoholic fermentation, 

 and cause a relatively higher amount uf volatile acid to be 

 formed. The above results fully confirmed my exj^ectations. 

 The hindering factor in the fir.st exi:)eriment was the great con- 

 centration of sugar. 



11. fcniuvitatioiis with one Pure Culture (HuB.,) and Different 

 Alusts at Different Temperatures. 



Sterilized must was slightly diluted and concentratetl to 

 give three musts with respectively 20" B.. 23.3° B.. and 27° B. 



