WILL'S TORULA 295 



WILL'S TORULA 



Will * has isolated from the cooling apparatus and from the air in 

 breweries, etc., seventeen forms of Torula as follows: 



Will's. Torula No. 1. This species produces a thin, white, dull 

 scum and a very evident ring. It forms a very evident deposit at 

 the bottom of the culture flask. The scum and ring appear at the 

 end of the third day. The thermal death point of this yeast in beer 

 wort and water is 65 C. The cells are very small, circular in shape 

 like the typical Torula. A few elongated and sausage-shaped cells 

 may also be found. 



Will's Torula No. 2. The scum and ring look like those 

 in Will's Torula No. 1. The cells are oval and sometimes very elon- 

 gated in the form of a sausage. This species perishes at 60 C. in must 

 and water. 



Will's Torula Nos. 3 and 4. These species form a very thick 

 folded scum, of a whitish yellow color, and also a well-developed 

 ring. At the bottom of the culture flask there is an abundant sedi- 

 ment. The scum develops rapidly and covers the surface of the cul- 

 ture three days after inoculation. The cells are shaped like the typical 

 Torula. These two species are almost identical. They are distin- 

 guishable only by the degree of changes in culture media. Both are 

 killed at 60 C. in must and water. 



Will's Torula No. 5. This species is most often round or oval. 

 It yields a very thin scum of small islands and a slight ring. The 

 sediment is mucous and well developed. Under certain conditions 

 this yeast gives on beer wort a flowing appearance. The cells are 

 killed at 65 C. in must and water. 



Will's Torula No. 7. The cells are spherical with a spongy in- 

 terior and a very distended membrane. An abundant deposit is 

 formed at the bottom of the culture flask and on the surface a very 

 mucous scum. In cultures which are a little old, it forms a thick mu- 

 cous sediment filling the entire volume of wort which is changed into 

 a compact mass. The thermal death point is around 60 C. in wort 

 and water. 



Will's Torula No. 8. The cells are large, oval and often elon- 

 gated. A well-developed ring is produced, a feeble scum and a mucous 

 irregularly developed sediment at the bottom of the culture flask. 

 The thermal death point in beer wort and water is 60 C. 



Will's Torula No. 9. The cells are very small and oval with 

 some elongated to the shape of a sausage. A feeble ring is formed, 



1 Will, H. Beitrage zur Kenntniss der Sprosspilze ohne Sporenbildung. 

 Zeit. f. d. Ges. Brauw. 26, 1903; 19, 1907; Cent. Bakt. 17, 1907; 21, 1908. 



