474 



EXPEEIMENT STATION EECOED. 



In another case tlie milk was chilled to 32°, and placed in the open air at a 

 temperature of from 4° above to zero for 30 hours. A small sample was kept 

 unfrozen in an ice- box to control the acidity. The can appeared as before, and 

 after separating and testing the various parts they were left for 3 days at about 

 39° to thaw and be remixed. The results were as follows: 



Chemical and physical constants of milk partially frozen at 4° F. 



Specific 

 gravity. 



Acidity. 



Original mUk 



Upper layer (0.6 qt.) 



Liquid center (2.5 qt.). . 

 Solid ice on sides (7 qt.). 



Remixed 



Unfrozen control 



1.0318 

 1. 0256 

 1.0534 

 1. 0201 

 1.0320 



Per cent. 

 6.2 

 8.2 

 11.0 

 3.8 

 7.2 

 7.0 



The milk was not changed by freezing in any manner perceptible to smell 

 or taste, nor to the peroxydase reaction. The author warns the police in- 

 spectors to be careful in taking samples of milk in frosty weather, and sug- 

 gests prohibiting the sale of partiallj^ frozen milk. 



[A froth dispeller] {Dairy, 23 (1911), No. 276, p. 325, fig. 1; N. Y. Produce 

 Rev. and Amer. Cream., 33 (1912), Xo. 21, p. 8S■'^). — ^A description is given of 

 a centrifugal machine for separating air from milk and milk froth. 



In appearance it resembles the Alfa separator. The milk in its attempt to 

 leave the bowl encounters paddle-shaped ribs in the space between the disks 

 and is sent through this space in a thin layer out of the bowl into the cover, 

 which it leaves by an outlet therein. The air which is separated from the 

 milk escapes from the bowl by passing out of the bottom disk and ascends into 

 the atmosphere. As the milk leaves the machine at a considerable force it can 

 be elevated, if desired, over a cooler without the aid of a pump. The air is 

 prevented from issuing with the milk by means of a regulating tap attached to 

 the milk outlet pipe. 



When separating pasteurized milk the froth dispeller is arranged to receive 

 the milk from the pasteurizer and feed it to the separator. When cooling 

 pasteurized milk the froth dispeller receives the milk from the pasteurizer and 

 elevates it over the cooler. 



Is it a menace to humans to drink milk obtained from cows affected with 

 tuberculosis of the udder? E. Ungermann (Tuierkulose Arb. K. Gsndhtsamt., 

 1912, No. 12, pp. 213-264). — In some cases no traces of tuberculosis could be 

 found in people who were accustomed to use tuberculous milk, though in other 

 instances the results were affirmative. The conclusion is reached that tubercu- 

 lous milk is a source of infection, but that a still greater danger is the con- 

 traction of the disease from human tuberculous patients. 



Eeport from the bacteriological department, 1911-13, J. Golding and W. 

 Sadler (Midland Agr. and Dairy Col. Bui. 8, 1911-12, pp. 67-78).— This con- 

 sists of brief notes on defects of milk and milk products. 



Bacillus lactis viscosus was found to be the cause of a sample of ropy milk. 

 A copper taint in milk was due to the use of a cooler from which the tin had 

 been largely worn off. A burnt taste in milk was traced to the presence of 

 Bacterium lactis addi. Milk sold as sterilized had turned yellow and was 

 found to contain a spindle-shaped organism, forming large spores quite resistant 

 to heat. A yellow discoloration of Stilton cheese was ascribed to the presence 

 of an abnormal amount of tyrosin. 



