268 



E. B. FRED AND W. H. PETERSON 



produces acid more slowly than Culture 124-1, does not favor 

 the growth of the pink yeasts. Perhaps the beneficial effect of 

 inoculation on pigment production is due to the rapid destruc- 

 tion of the easily fermentable sugars and to the change in reac- 

 tion. This combination of conditions no doubt reduces greatly 

 the complex of the bacterial life and thus favors the development 

 of the wild yeasts. 



TABLE 4 

 The relation of acid forming bacteria and pink yeast to the production of pink 



sauerkraut 



* Acetic and lactic acids equivalent to 109 cc. O.In per 100 cc. of juice. 



The stimulating effect of acids on pigment production is 

 further indicated by the results obtained in containers Nos. 

 10 and 12 where acetic and lactic acids were added to unin- 

 oculated cabbage and to cabbage inoculated with yeasts. The 

 quantity of acid added was approximately that found in a moder- 

 ately ripened kraut. Pigment was observed after seven days 

 which is about the earliest appearance of color in any of the 

 experiments. 



