DAIRYIXG 



iiSt 



913 - Factors Affecting the Fat Content of Whole and Skim Milk. — guthrik e. c. and 



SUPPLEE G. C ill Cornell University, A^^ncultiiral Experiment Station of the College of 

 Agriculture, Depart me nt of Dairy Industry, Bulletin 2,(>o, pp. 271-289, tig. 117-125. Ithaca, 

 X. Y., April 191=). 



Several factors influence the fat content of cream obtained with a sep- 

 arator (independently of the variations of such content due to displace- 

 ments of the regulating device), w^: the temperature, .speed, rapidity of 

 feed, content of fat in the full cream milk, the variations in the quantity of 

 liquid (skim milk or water) which is passed through the drum of the separa- 

 tor at the close of the operation in order to force out the residue completely, 

 or, as is the case in practice, in the quantity of whole cream milk used for 

 this purpose, and the quantity of milky deposit formed. 



In order to determine the nature of these influences, the writers un- 

 dertook the experiments described in the Bulletin in question, making use 

 of different types of separator. The results proved the following : 



The influence of low temperatures (the operations were conducted at 

 temperatures varying from 21.1° to 32.2° C) on the percentage of fat in the 

 milk and the skim milk varies with the different types of separator. 

 The results, which are particularly conclusive for two t^^pes of separator, 

 seem to demonstrate that, all other things being equal, when the tem- 

 perature is lowered the quantity of cream extracted is diminished, but that 

 the weight of the fat contained in this cream remains comstant. 



With some types of separator the percentage of fat in the cream varies 

 markedly even for a variation of 10 revolutions per minute in the revolu- 

 tion counter (corresponding to i 500 revolutions per minute in the drum); 

 on the contrary, other types exhibit this influence in a much less degree. 

 In regard to the types of separator which showed variations in the percent- 

 age of fat, the writers find that when the speed diminishes the weight 

 of the cream obtained increases, which was obvious a prioy\ but that the 

 weight of fatty matter contained in the cream still remains constant. A 

 variation of 10 revolutions per minute in the counter had no appreciable 

 influence on the percentage of fat in the skim milk. The percentage of 

 fat in the cream is practically directly proportional to the percentage of 

 fat in the full cream milk. It increases slightly when the milk enters the 

 drum slowly. The variation in the quantity of full cream milk utilised, or 

 in the quantity of liquid employed to force the remaining cream out of the 

 drum at the end of tlie skimming, has but little influence on the percentage 

 of fat in the cream. 



The milk deposited has only an insignificant influence on the percent- 

 age of fat in the cream and the skim milk, provided its quantity is not 

 sufficient to choke up the passage through the drum. 



914 - Metallic Taste in Dairy Industry Products. — gutkrie e. s. in Cornell University 



Agricultural Experiment Station of the New York State Colle'^e of As.ricuUure, Department 

 01 Daily Industry, Bulletin 373, pp. 605-64^, 19 tables. Ithaca, New York, April i()i6. 



The metallic taste, which influences the price of dairy industr>' pro- 

 ducts, was first detected in iqoi. The writer entered into corres])ondence 

 with a large number of experts in order to determine exactly what is to be 



