DAIRY FARMING- — DAIRYING AGROTEi ll.W. 1185 



The author has also found polarization of the milk serum of value for this pur- 

 pose. While the normal index of refraction lies between 5 and 5.5, it was found to 

 be 1.2, I, and 0.73 in the case of diseased animals. The freezing point, however, 

 remained constant. 



The care of composite milk samples, I. < '. W'i.i i» i New Hampshin Sta. Bui, 

 196, pp. 181 184, figs. 5). Brief notes are given on the taking of composite milk 

 samples ami on preserving them with formalin, potassium bichromate, or corrosive 

 sublimate. 



On the combination of lactic acid with casein in lactic fermentation, < '. 

 Richet {Oompt. Rend. Soc. Biol. [Paris], 60(1906), No. /;, pp. 650, 651). When 

 milk was allowed to coagulate spontaneously the curd was found to fix aboul 5 times 

 the amount of lactic acid contained in the same volume, of w hey. 



A test of tin can separators, C. II. Ecklks Missouri Sta. Bui. 68, pp. 

 figs. /'). -Tests were made of 3 forms of so-called separators which consist of 2 cans 

 one within the other. The milk is placed in the inner can and cold water in the 

 outer can surrounding the milk. 



The average results of 4l> trials with these cans showed that the -kim milk con- 

 tained 1.39 per cent of fat, equivalent to a loss of 22.56 per .-cut of the fat The:; 

 patented cans were compared with shallow pans, a dilution can, the centrifugal 

 separator, and a homemade can. Under the conditions of the comparison the shal- 

 low pans gave better results than either the dilution or double can-. The homemade 

 can costing Sl.'iO irave equally <rood results as the patented can- costing from 4 »> 



to no. 



Creamery problems, C. L. Beach (Connecticut Storrs Sta. Bui. JO, pp. $& 

 Of 1,362 patrons of 18 creameries in 1903, 256, or 19 per cent, wrere using centrifugal 

 separators, while the remainder were using the Cooley system of cream raising. 

 Comparative tests were made of these 2 methods. 



The average of 13 samples of skim milk by the Cooley system Bhowed the presence 

 of 0.27 per cent of fat, and the average of 36 samples of separator skim milk showed 

 the presence of 0.056 per cent. It is estimated that with a herd of 10 cows the hand 

 separator effects a saving of 825.48. Five types of centrifugal separators were com- 

 pared, the fat content of the skim milk ranging from 0.038 to 0.076, which difference 

 for a herd of 28 cows is estimated as equivalent to $7.95 for one year. 



The fat content of 10 samples of skim milk was determined by gravimetric analysis 

 and by the Babcock test, using 17.6 <•<•. and 25 rv. of acid. The average results for 

 the 3 methods were, respectively, 0.144, 0.046, and 0.063 percent. Even with the 

 excess of acid the Babcock readings were much lower than the gravimetric deter- 

 minations. 



Readings of Babcock tests were made at temperatures of 130 and 180° F., the 

 average difference on 10 samples being 0.42 percent. This emphasizes the impor- 

 tance of making the readings at a uniform temperature. 



' Variations in the weight of 18 cc. of cream containing different percentages of fat 

 are given in tabular form to show the importance of weighing samples. 



In 14 experiments a -tarter made from a pure culture was compared w ith a skim 

 milk starter. The average score of the butter from the 14 churnings when the pure 

 culture starters were used was 94 and oi the butter from the churnings ripened with 

 skim milk starters 0-1.1. A table shows the bacterial content of 12 samples of butter, 

 of the cream from which the butter was made, and of the starter used in ripening 



the cream. 

 Creamery cold storage, .1. A. Ruddick (Canada Dept. Agr., Dairy Comr. Branch 



Bui. 10, pp. 14, ph. .').— This furnishes information OH the subject of creamery old 

 storage and embodies the results of recent experiment- conducted for the purpose of 

 testing various material- used for the purpose oi insulation. Specifications am 



4113— No. 12—00 o 



