430 



STATE BOARD OF AGRICULTURE. 



From the above, it will be noted that the lactic bacteria were sub- 

 jected to a process of "rejuvenation" if it may be so called, which was 

 most marked in llie case ol' Lactone, the initial inoculum of which was 

 a litmusniilk culture 24 days old and neither curded nor very acid. 

 This rejuvenating process occurred in another mixed culture of the yeast 

 LZ and Lactone, the data of which is found in the next table. 



This culture of Lactone, originally isolated from a dry commercial 

 starter, had been kept in litmusniilk culture in cold storage at 

 5° — 10°C. for 7 weeks. When taken out, it was but very slightly acid, 

 but curded in 3 days. A transfer from this culture, just curded, and 

 from a culture of the yeast LZ was made into LM)I) cc. sterile milk, a 

 transfer of Lactone being made into a litmus milk tube for a check. 



2 da: — 'Mixed culture curded; check not curded. 



3 da : — Check curded. 



5 da : — Yeast LZ becoming evident. 



TABLE XHI. 

 Lactone plus Yeast LZ in MUk. 



Mixed Culture. 



Test Cultures. 



♦Plated from test culture and isolated 2 colonies; both curded typically withm 24 hours. This pure culture has retained its 

 rctivity tor over three months, in fact is more active than Strain No. 2. 



As noted in Tables XI and XIII, Lactone was seemingly rejuvenated 

 so the experiment was repeated to check the results already obtained 

 using as many different cultures of weak lactic bacteria as were avail- 

 able. The ones obtained are as follows: Lactone, a 3 weeks old culture, 

 not acid and not curded; Stock lactic, a bacterium ])roducing almost no 

 acid, does not curd milk but does possess slight litmus-reducing proper- 

 ties; HA, a weak lactic bacterium, curds in 3 days; FC, a less active 

 than HA ; and L, a 9 weeks old lactic bacterium which had produced 

 but little acid and had not curded, the culture used in this experiment 

 was the original culture isolated from milk. In each case, 1 cc. of a 

 14 weeks old wiiev culture of yeast LZ was used. 



