( 29 ) 



industry are always found lactic acid ferments of the genus Lacto- 

 bacillus, mostly of Lactococcus too. These lactic acid ferments alone 

 determine the character of the "leben rai'b" of Egypt, ') of the 

 "yoghurt" of Bulgary,') and probably also that of the "prostokwacha" 

 and the "véranetz." of Russia, which Mktchnikoff mentions. In the 

 "kephir'' of the Caucasus, the "koumys" of Central Asia, 3 ) and the 

 "mazun" of Armenia, 4 ) occurs moreover, lactose yeast, which may, 

 however, under certain circumstances he wanting, without the 

 character of these beverages being lost. All other microbes, which 

 are mentioned in literature as occurring in the said beverages or 

 their ferments, such as Oidium, Mucor, oilier moulds, torula, red 

 yeast, vinegar bacteria, butyric acid ferment, proteolytic bacteria, 

 are only present by deficient preparation, so that it may be said 

 that in all examined cases a pure lactic acid fermentation proves to 

 be the wanted process, whilst eventually also an alcoholic ferment- 

 ation is wished for or suffered 5 ). 



Hence, in the commercial preparations which start from yoghurt, 

 onl}' lactic acid ferments are cultivated. I have in particular inves- 

 tigated the products of "Le Ferment", mentioned beneath, as also a 

 substance, sold as "maya" or Bulgarian ferment. ") to which my 

 attention was drawn by Dr. De Lint at Scheveningen. Here 1 will 

 shortly describe the latter preparation. 



It consists in a yellowish strongly acid reacting powder, composed, 

 after chemical, microscopical and bacteriological examination, of caseine 

 lactic acid, lactose, fat and lactic acid bacteria; it is evidently nothing 



!) Annates de l'Institut Pasteur. T. 16. p. 65, 1902. 



2 ) Massol et Grigoroff, Revue medicate de la Suisse romande 1905 p. 716. 

 Bertrand et Weisweiller, Action du ferment Bulgare sur le tait. Ann. de l'Institut 

 Pasteur, T. 20, p. 977, 1906. 



3 ) For Kephir and Koumys see Weigmann in Lafar Technische Mykologie. Bd. 2. 

 p. 128. 1905. 



*) Centralblatt für Bacteriologie, 2le Abt. Bd. 15, p. 577, 1906. 



6 ) The study of literature leads at first view to a quite other result, as many 

 microbiological descriptions are made by beginners, not sufficiently acquainted with 

 the properties of lactic acid ferments, and who have attributed an exaggerated 

 weight to the different kinds of infections named above. 



c ) On the bottle stands: Maya bulgare, Société de la maya bulgare, Garnier 

 & Co., Paris, 16 Rue Popincourt. The Société de Pury, Montreux, brings into 

 commerce a ferment of the same nature under the name of "maya bacilline" 

 and the Société Henneberg, Geneva, a liquid preparation as "lacticose". Besides 

 there are to be had in Paris Lactobacilline de Metchnikoff in "Le Ferment" 

 Fournisseur de l'Assistance publique, 77 Rue Denfert-Rochereau, who sells also the 

 "Biolactyle" of Fournier and the "Bacilline paralactique" of Tissier (the preparations 

 of this firm make a very good impression). 



