480 EXPERIMENT STATION RECOED. [Vol.38 



which increase the percentage of casein in the total nitrogen also increased the 

 galactase content. The ripening of cream did not increase the rate of proteo- 

 lysis. No oxidase was found in milk or butter. Only one sample of butter 

 gave any evidence of lipa.se at the end of four days at 40° C. The enzym con- 

 tent of butter is very small, because of the high dilution in fat. Expressed on 

 the basis of total nitrogen the butter examined contained as much galactase as 

 fresh whole milk, twice as much catalase, but only one one-hundred-sixtieth as 

 much peroxidase. The cold storage of butter weakens the peroxidases, but has 

 little effect on the catalase and galactase." 



It is concluded that enzyms are not to be considered as a factor in the 

 deterioration of butter during cold storage. 



A list of the literature cited as included. 



Sugg'sstions for a standard for butter, H. Veeder, R. C. McRIanus, W. P. 

 Jones, and G. P. McCabe (Chicago: Sw-ift iG Co., 1917, pp. 15). — As a result of a 

 study of the provisions of existing laws, decisions of the courts, and other data, 

 the following standard for butter is suggested : 



" That the only ingredients which may be used in the manufacture of stand- 

 ard butter are those named in tbe law of August 2, 1886. These ingredients 

 are milk or cream or both, with or without common salt, and with or without 

 additional coloring matter. That milk or cream used in the manufacture of 

 standard butter shall be (1) pasteurized, or (2) from properly tuberculin- 

 tested, nonreacting herds. That milk and cream used in the manufacture of 

 standard butter shall not be filthy, putrid, or decomposed within the meaning 

 of the Food and Drugs Act, and that standard butter shall not be made to 

 contain abnormal quantities of salt or curd, and shall contain a definite mini- 

 mum percentage of butter fat. For the infortnation of butter makers, thei-e 

 should be a suggestion as to what are the variable limits in standard butter 

 of the normal quantities of such substances. That no standard butter shall 

 be made from butter or butter fat in which any substance whatever has been 

 used to deodorize or remove rancidity. That in the manufacture of standard 

 butter no process or material shall be used which has the effect of causing the 

 butter to absorb abnormal quantities of water, milk, or cream. For the in- 

 formation of butter makers there should be a suggestion as to what are the 

 variable limits in standard butter of normal quantities of moisture. That, if 

 it shall be found that small quantities of lime, or of sodium carbonate, or other 

 alkaline salts may be used as ingredients in butter making without violation 

 of the Food and Drugs Act, such butter shall not be standard butter, but 

 shall be defined as ' neutralized butter ' or ' limed butter ' and shall only come 

 within the terms of such definition when the butter or butter fat from which 

 the product is made has not been deodorized, or had rancidity removed or 

 masked ; otherwise it is adulterated butter." 



Making butter on the farm, W. White ( U. S. Dept. Agr., Farmers' liul. 876 

 (1917), pp. 23, figs. 18). — Detailed directions for making butter under farm con- 

 ditions are given, togetlier with notes on the causes of difficult churning and 

 the equipment needed for butter making on the farm. A plan for a dairy house 

 is included. 



VETERINARY MEDICINE. 



Pathog'enic microorg'anisms, W. H. Paek and Anna W. Wiixiams (Neto 

 York: Lea d Febiger, 1917, 6. ed., enl. and rev., pp. X+17-709, pis. 9, figs. 209).— 

 In the enlargement and revision of this work (E. S. R., 21, p. 579) the authors 

 were assisted by C. Krumwiede, jr., and others. 



