154 Report OF THE CHEMIST OF THE 
fermentation and is comparable to the addition of a sour-milk 
“starter ” to cream in order to produce ripening, that is, forma- 
tion of lactic acid. The practice of adding “ mother ” of vinegar 
to cider is based upon the same explanation. Effort should be 
made to have some “ mother” in the vinegar added. 
In another experiment (15), vinegar was added when the apple 
juice had been fermenting two months, and the alcoholic fer- 
mentation was still incomplete. In this case, the acetic ferment 
thus added appeared to exercise no influence upon the formation 
of acid. 
The influence of separating the clear portion of cider from 
sediment upon- the acetic fermentation.—In the experiments 
numbered 1 to 10, a study was made of the effect of separating 
the clear portion of the cider from the sediment after the alco- 
holic fermentation was completed and in some cases the clear 
liquid was siphoned off and only this clear portion used for the 
acetic fermentation. Even though the fresh apple juice was in all 
cases carefully strained through linen cheese cloth, much insoluble 
matter remained, which settled to the bottom of the cask during 
the alcohol fermentation. In the case of the strained and 
siphoned ciders the casks were cleaned before replacing the 
ciders. 
The ciders numbered 1 and 8 were strained, those numbered 
2, 4, 5 and 6 were left undisturbed, while in 7, 8, 9 and 10 the 
clear portion was siphoned off and this alone used. The results 
are presented in the following table: 
TaBLE XIII.—PERCENTAGE OF ACID IN CIDER VINEGAR WHEN 
STRAINED AND UNSTRAINED. 
Srorep IN Coon CELLARS. SroreD In WARM Room. 
AGE. 
Siphoned. | Strained. | yok a Siphoned ‘| Strained. ely, a: 
Months. Per ct. Per ct. | Per ct. Per ct. Per ct. Per ct. 
BNe Sete acct eed pets ee 0.57 0.56 | 0.65 On55 0.55 0.56 
(9 te te RA. Ere 0.39 d bee S| 0.37 0.83 0.62 0.38 
LOSS Sle Soe le 0.64 TAB 0.39 1.60 1.05 0.70 
11S ha A ae 5 Saeercee Canoe yee 1.05 2.36 | 0.42 3.69 4.01 4.45 
DM ef She shes eacshe vere sys 3.76 3.95 0.37 7.09 7.03 9.24 
A eee serene Ore 5.70 Ost 0.80 8.50 9.08 —-. 
Di: isa h oe e ee cine blots 6.05 6.41 1.48 7.08 SS 9.5; 
QO RR Streeter 6.16 6.49 1.42 8.80 8.73 —! 
SOa cia tou eee ote 5.97 Cpovitel 4.24 9.96 10.00 — 
AAT Sa. et hate cere enaaeh 6.15 7.97 | 6.83 10.51 11.05 9.82 
a ee a 
