igo AIDS TO BACTERIOLOGY 



the albumin of milk, forming peptones and ammonium 

 butyrate. 



Clostridium butyricum (B. amylobacter) is a long, thick, 

 motile, anaerobic rod, often forming chains. A terminal 

 pore is formed. Butyric acid is formed in solutions of 

 sugar?, lactates, and in cellulose-containing plants. The 

 young organisms of the form described by Prazmowski 

 contain granulose, which stains blue with iodine. (See 

 also p. 87.) 



Greasiness in Cider . Kayser finds this disease to be 

 caused by an anaerobic bacillus which ferments sucrose 

 with production of carbon dioxide, alcohol, lactic and 

 acetic acids, also mannitol and laevulose. 



Fermentation of Cream. ' Natural starters ' for ripen- 

 ing cream naturally contain a mixture of organisms, 

 those producing lactic acid being in greatest number. It 

 is now commonly the practice to use an artificial starter 

 after a preliminary Pasteurisation. In some cases the 

 organism employed appears to be Streptococcus lacMcus. 

 Similarly, cultures may be added to the cream to produce 

 a good aroma in the butter. 



Butter is liable to certain bacterial diseases: turnip 

 flavour (B. fostidus lactis), bitter butter (B. fluorescens 

 liquefaciens, Oidium lactis, and other organisms), etc. 



Bacteria in Cheese Manufacture. Conn considers that 

 two moulds are necessary for the production of Camem- 

 bert cheese a white Penicillium (candidum ?), and 

 Oidium lactis (p. 170). Slimy whey, containing Strepto- 

 coccus Hollandicus (see p. 219), is used as a starter for 

 Edam cheese. Penicillium glaucum is the chief agent 

 employed in the ripening of Roquefort, Stilton, and Gor- 

 gonzola cheeses. Moulds also play an important part in 

 the production of Brie and other soft cheeses; the growth 

 of certain organisms is encouraged upon the surface of 

 these cheeses, so that the special ferment which they pro- 

 duce can penetrate the body of the cheese and bring about 

 certain characteristic changes. 



Tobacco-Curing. The leaves are suspended in barns, 

 when the leaf enzymes convert the starch into sugar. 

 The browning of the leaves which takes place during this 

 period is a complicated process, and is the outward expres- 

 sion of a large number of very little understood processes 

 which are not bacterial. The dried tobacco-leaves are 



