CHEESE 369 



portion than 3 or 4 : 96 or 97, the ripening is likely 

 to be unsatisfactory and result in the production of a 

 cheese of poor flavour and aroma. 



Freudenreich isolated from Emmenthal cheese several 

 cocci and rod-shaped bacteria which produced lactic acid 

 and curdled milk, and at the same time broke down the 

 casein into soluble proteins when the acid was neutral- 

 ized with chalk. Gorini states that some bacteria act 

 as lactic acid producers at higher temperatures, and 

 peptonize casein under the cooler conditions of the 

 cheese store-rooms. 



(c) Weigmann and others consider that the ripening 

 of cheese is a much more complicated problem than that 

 which is suggested by Duclaux and Freudenreich. Many 

 workers hold that the specific lactic organisms do not 

 ripen cheese. It is impossible under ordinary conditions 

 of manufacture to avoid the access of these bacteria to 

 the milk and fresh curd, and they find the latter a suit- 

 able medium in which to grow and multiply extensively, 

 but their influence upon the ripening is indirect only. It 

 is suggested that they destroy or check some kind of 

 bacteria which are detrimental to the normal develop- 

 ment of taste and flavour, and produce an acid condition 

 which is essential to the growth of the peptonizing 

 group and the action of their enzymes. In some 

 instances sour whey or other acid starter is added during 

 the manufacture of the cheese in order to ensure that the 

 ripening shall proceed in a normal manner. Ripening 

 is assumed to be a kind of symbiotic fermentation in 

 which the lactic organisms use up the oxygen and pre- 

 pare the ground for the anaerobic species which are 

 supposed to be the bacteria chiefly responsible for the 

 degradation of the proteins in the cheese. Weigmann 

 2 A 



