: ce — 
We 
an 
98 Report oF THE CHEMIST OF THE 
gave a very satisfactory product in respect to clearness of whey, 
rapidity of its separation and texture of curd. 
Three special experiments were made to test the action of 
different temperatures upon the coagulation of milk-casein by 
hydrochloric acid. In each of these experiments we used 20 
pounds of separator skim-milk and added 0.25 per ct. of hydro- 
chloric acid. The results are given in the following table:— 
TABLE V.—SHOWING INFLUENCE OF TEMPERATURE ON COAGULATION 
OF CASEIN BY HyprocHLoric ACID. 
| | 
N f Amount of | Tempera- Taeush of } 
0. O' | Amount of | hydrochlo- | ture of milk iced for .| . 2iwieon Moisture 
ater milk used. |. ric acid when acid q ar poh cheese. in cheese. 
see used. | was added. Again | 
| 
Pounds. | Per ct. | Degrees F. | Hours. Min.} Pounds. Per ct. 
1 20 | 0.25 | ; 60° 20 == | 2.9 72.4 
2 20 0.25 | 70° 1 =| 3.9 (ouk 
3 20 0.25 | 80° — 30 | 3.85 Va. 
| | 
The data embodied in Table V show that—(a) there was little 
difference in the yield of cheese or moisture in the cheese when 
the milk was at different temperatures at the time the acid was 
added; (b) the time required for the curd to drain free from 
whey was greatest when the lowest temperature was used, de- 
creasing with increase of temperature. From these figures, it 
appears that good results may be obtained at any temperature 
between 70° F. and 80° F. (21° C. and 27° C.). 
COMPARISON OF RESULTS OF MAKING COTTAGE CHEESE, BY DIFFERENT 
METHODS. 
In the following table we present the summarized results of . 
work done by us in making cottage cheese (1) by natural sour- | 
ing of milk with and without the addition of a starter, (2) by 
coagulating milk with starter and rennet, (8) by direct addition 
of lactic acid, and (4) by direct addition of hydrochloric acid. 
The same milk was used in experiments 2, 3, 4 and 5. 
