New York AGRICULTURAL EXPERIMENT STATION. 145 
THIRD EXPERIMENT: EFFECT OF TREATING MILK WITH CARBON 
DIOXIDE GAS UNDER PRESSURE OF SEVENTY POUNDS. 
In this experiment, fresh skim-milk was charged ‘with carbon 
dioxide gas under a pressure of 70 pounds to the square inch. In 
charging the milk, we made use of the apparatus of a local bottler 
of soda water. Pint bottles were used which were closed with 
patent tin and cork caps (Plate VI, fig. 5). The bottle-filling ma- 
chine was set to deliver carbon dioxide gas under a pressure of 70 
pounds. ‘The bottles of skim-milk, half full, were placed in the 
machine and charged, after which they were shaken for a short 
time, and the caps removed to allow the carbon dioxide and air 
to escape. hey were then charged again and, by repeated charg- 
ing and opening three or four times, a comparatively pure atmos- 
phere of carbon dioxide under a pressure of 70 pounds to the square 
inch was obtained. This method was found to be'more trouble- 
some and less effective than the method used later (p. 148). 
In this set of experiments, the results of which are given below 
in Table II, the milk used in all the bottles was from one lot. The 
bottles of milk were kept at 40° to 45° F. 
Taste IJ.— SHow1ine Amount or Acip In Mitk, Kumiss AND CARBONATED 
; MILK. 


Milk, | Milk, | Milk, | Milk, Milk 
and 






Milk Milk : 
ae , Milk yeast | yeast | yeast | yeast 
AGE. Milk un-jheated | and 20 and and 5 | and 10 | and 20]! and 40 70 Ibs. 
treated. to grams : carbon 
103°F. | sucrose.| Yeast. | 8tams | grams | grams | grams | 4.0346 
sucrose. /sucrose. |sucrose./sucrose. |G. 5. 
Days, Per ct. | Per ct. \\ Per ct.| Per ct.| Perct.| Perct.| Per ct.| Per ct.,| Per ct. 
Terese. + sues 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18 
ed eee 0222 0.36 On21 0.25 0.30 0.30 | aQ:29 | a0.32 0.25 
=) Say Ce Re 0.23 | a0.54 0.25 | c0.90 |} 60.49 | a0.43 | 60.33 0.32 a0 .29 
Nene EL, COPGT WIGOESBHT CONRSBAE 2 St2 c0.86 | b0.45 0.36 | a0.36 OBZ a 
2 Soe ee aaa ae RS alee OES Sha ene en MS c0.84 0.55 | a0.438 0.40 
PRE Raye ots ole FAME See ok Gio el e keel tts 2a c0.72 | a0.65 b0.43 
eee ee ns ee Lee eee ne es her a0.58 b0.54 
ee Re ie en em ber aia eis cae. Nh custo nace? [Li dos Seaton’ Weick trotters. Ve thchiatsds a0 .54 b0.58 
Ee Nts ex oy url ee eH eed shee 2 oes ove ceo |i oe hom echt law & Seeumy Mbaiers eve. 6 a0 .65 b0.54 
RR ET AG PL. ee poncn a lidexsr othe Mi. coe svat tiltGn eer, |) ees ce [te cuete 2. Peeideate b0.58 
REE RLS Sohn ce eA dee | ee i cit emda b0.65 
Cree Ne, CSE OKT eS 60.0. 2 A Te COA aL) (SR ASESE LM hore? Lae epee nS aes c0.83 


a Coagulated slightly on boiling but not sour. 
b Coagulated almost completely on boiling but not tasting sour, 
c Coagulated completely without heating; sour. 
The results in Tables I and II show a general agreement, indi- 
cating that in the milk containing the largest amount of sugar 
with yeast and, therefore, the largest amount of carbon dioxide, 
the coagulation of the milk by souring was delayed beyond the 
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