10 BULLETIN 148, U. S. DEPARTMENT OF AGRICULTURE. 



It is worthy of note in this connection that the good cheeses of 

 this series, with one exception, developed very large, though too 

 many, eyes; in fact, the cheeses were hurried to cold storage to 

 prevent cracking from an excessive growth of e} r es. No other cheese 

 made at the factory the same season had a sufficient eye develop- 

 ment, and no factory is able to secure a satisfactory eye growth so 

 early in the season as this work was done. The unusual develop- 

 ment of eyes in the cheese made in this experiment was secured only 

 by the use of the cultures. The culture in this case was obtained 

 from one of our own winter-made cheeses that would rival any im- 

 ported in eyes, texture, and flavor. It was ground up and incubated 

 in whey for 24 hours. In these experiments unusually heavy cheese 

 starters were used, which possibly accounts for too great a growth 

 of eyes. The cheese made in this factory, after the experiments 

 were completed and when the culture was not used, did not in any 

 case show a satisfactory growth of eyes. Some cultures of Bacillus 

 bulgaricus favor the growth of eyes more than others, but the use 

 of starters for securing eyes in Swiss cheese will be discussed in a 

 subsequent paper. 



From the results of the experiments with Bacillus bulgaricus cul- 

 tures it would appear that with their proper use in starters, Swiss 

 cheese can be made in winter as well as in summer. It also seems 

 practicable to make cheese once a day. However, B. bulgaricus cul- 

 tures will not be a " cure-all " for any condition of milk which care- 

 less farmers may be able to bring about, but if the milk receives 

 as good care as it receives when the best quality of cheese is made 

 at the present time, and the evening milk is cooled at once after milk- 

 ing so it will not have developed acid when delivered to the factory, 

 there should be no serious difficulty with the help of a good starter in 

 making good Swiss cheese once a day and every day in the year. 



AMOUNT OF STARTER TO USE. 



We have found that 3 per cent of starter can be used without any 

 indication of harmful results in the ripening cheese. Probably a 

 greater amount of a weak culture or of a starter with a low acid 

 content at the time of use could be employed. But 3 per cent of a 

 strong culture with a high development of acid in the starter is 

 apparently all that it is safe to use. More than 3 per cent of starter 

 has in some instances apparently suppressed all tendency to form 

 eyes, while the use of as much as 3 per cent has no apparent injurious 

 effect on eyes, texture, or flavor. With a strong, active culture of 

 Bacillus bulgaricus, 2 per cent of starter would undoubtedly prove 

 more than sufficient to insure a perfectly solid cheese, excepting 

 under the most extreme conditions of a poor milk supply. It is 

 suggested that this amount be used, since it can be safely employed. 



