RED YEASTS AND BLACK YEASTS. 401 



of Torula imparts a full, and even pappy, flavour to beer ; and, 

 in certain circumstances, this may well be the case. Torula 

 species occur almost invariably in beer worts cooled and aerated 

 in vessels that are not enclosed and protected from atmospheric 

 infection. Experience teaches, however, that these organisms 

 do not develop to any considerable extent, because, as shown by 

 Will, most of them are suppressed entirely, or else greatly 

 checked in their development, by the primary and secondary 

 fermentations. It is a matter of experience that beer maladies due 

 to Torulacece are extremely rare, and therefore these organisms 

 cannot be regarded as injurious to beer in general. According 

 to Will's researches, the addition of yeast to cultures containing 

 certain mucinous species of Torula results in the so-called 

 " boiling " fermentation (see p. 184, vol. ii.), in which the usual 

 fine head on the liquid is replaced by a few very large bubbles. 

 According to the concordant reports of N. HJ. CLAUSSEN (I.) and 

 H. SEYFFERT (II.), certain species of Torula play an important 

 part in the preparation of English beers. This group, known 

 as Brettanomyces, is indispensable for the flavour and aroma 

 developed in English beers by ethereal products formed during 

 secondary fermentation. 



Certain Torula species are valuable to the cattle-breeding 

 mountaineers of Caucasia, as well as to the inhabitants of Armenia 

 and the nomadic tribes of South-East and Southern Russia, since, 

 in collaboration with certain bacteria, they serve in the preparation 

 of important food-stuffs and delicacies, e.g., kefir, koumiss, and 

 inazun. Further particulars on this point are furnished by 

 E. VON FREUDENREICH (XI.) and A. KALANTHAR (I.). Harrison's 

 Torula amara imparts a disagreeable, bitter taste to milk and 

 cheese ; and, according to L. A. ROGERS (II.), tinned butter is 

 endangered by species of Torula. 



301. Red Yeasts and Black Yeasts. 



Small as our knowledge is of the, usually colourless, Torulacece 

 described in the preceding paragraphs of the present chapter, it is 

 still less as regards the budding fungi that attract the eye by 

 their more or less intense and variously shaded red colour. These 

 are called by different authors " pink yeast " or " red yeast," some 

 even classifying them with the genus Saccharomyces, though the 

 majority do not form spores. The earliest attempt at a thorough 

 investigation of these budding fungi was made, at a comparatively 

 recent date, by F. A. JANSSENS and A. MERTENS (I.), with a species 

 described as " red Torula" 



Red budding fungi have long been known. At first they 

 were described by FRESENIUS (I.) under the name Cryptococcus 

 glutinis ; and, subsequently, SCHRODER and COHN (I.) grouped 

 similar organisms (termed " pink yeast " by Cohn) with the 



