176 EXPERIMENT STATION EECOED. 



the fact that the loss of elasticity of the curd at the higher temperatures pro- 

 duced a less dense cheese with more widely distributed air spaces, and conse- 

 quently greater growth of blue mold, or that inhibitory organisms were de- 

 stroyed in the milk, thus permitting the freer growth of the mold. Cheeses pre- 

 pared from heated milli contained water 33.61 to 36.22 per cent, fat 32.36 to 

 34.53, insoluble nitrogen (probably unaltered casein) 2.49 to 2.91; and deter- 

 minations of acidity, expressed as normal sodium hydroxid per 100 gm. of 

 cheese, 13.2 to 20 cc. The heating resulted in a higher percentage of water in 

 the ripened product. The fat is consequently a slightly lower percentage, and 

 the higher acidity in the heated cheese may be due to the fact that more starter 

 was added in making the cheese. 



In the case of very rapid heating, the number of organisms in the milk was 

 not effectively reduced below 170°, but at this point the number was reduced to 

 one-fiftieth of the total, at 1S0° to one eighty-fifth, and at 200° practically all the 

 organisms were destroyed. There was a much greater reduction when the milk 

 was maintained at 150° for 15 minutes than when it was heated very rapidly to 

 170°. Complete sterility was not obtained at any temperature. 



It was found that there was a definite increase In the number of organisms 

 in the milk from the vat before any starter had been added and the number in 

 the milk as it came from the cooler, indicating that milk once pasteurized should 

 be handled as little as possible before it is put to the use for which it is intended. 



The manufacture of condensed milk, milk powders, casein, etc. — Discus- 

 sion of methods of analysis, R. T. Mohan {Jour. Soc, Chem. Indus., 34 {1915), 

 No. 3, pp. 109-113). — This is a discussion of the analysis of these various 

 products and the factors influencing their composition and quality. 



It is said that milk of different seasons will stand different temperatures, for- 

 tunately the highest in the summer. The fresh milk varies in composition with 

 the seasons, and hence the concentration also has to be varied to bring the 

 product up to standard. In June the solids in the fresh milk average 12.68 per 

 cent, in the condensed milk 25.81 ; in August 11.75 and 26.01 ; in November 13.40 

 and 26.62. It is said that swells, flat sours, and sweet curdling in evaporated 

 milk are due to understerilizition. Curdiness (other than sour curd) is due to 

 precipitation of the curd as a hard mass under the action of heat on a product 

 of high solids and acidity. The hard grains sometimes found in the bottom of 

 the cans consist of mineral matter, mostly calcium phosphate, precipitated owing 

 to overconcentration. 



VETERINARY MEDICINE. 



Collected papers from the Research Laboratory, Parke, Davis, and Com- 

 pany, Detroit, Michigan {Collected Papers Research Lai). Parke, Davis & Co., 

 Reprints, 2 {19U), pp. IV+289-590, pi. 1, figs. 100).— These papers, which 

 have been previou.sly published in various scientific journals, include articles on 

 hog cholera by W. E. King, R. H. Wilson, G. L. Hoffmann, and F. W. Baeslack 

 (E. S. R., 28, pp. 381, 482, 587; 29. p. 681; 30, p. 383) ; on canine distemper and 

 equine influenza by N. g. Ferry (E. S. R., 29, p. 682) ; and on tetanus by C. T. 

 McClintock and W. H. Hutchings (E. S. R., 29, p. 679). Other papers of interest 

 are : The Employment of Protective Enzyms of the Blood as a Means of Extra- 

 corporeal Diagnosis.— I, Serodiagnosis of Pregnancy, by C. P. McCord; Stand- 

 ardization of Disinfectants.— Some Suggested Modifications, by H. C. Hamilton 

 and T. Ohno ; and Correcting Water, by H. C. Hamilton. 



Castration of domesticated animals, F. S. Schoenleber and R. R. Dykstra 

 {New York: Orange Judd Company, 1915, pp. X+154, figs. 53). — A small hand- 

 book intended for the use of stock owners, students of agriculture, and veter- 



