- 554 - 



first competition is: The determination, by means of new experi- 

 ments made at any rate partly on man, of the comparative nutri- 

 tive value of raw and cooked milk (pasteurised, sterilised and dried). 

 In the event of an advantage being shown in favour of raw milk, 

 to determine the part played by the enzymes of milk in nutrition. 



S. H. COLLINS. The Transfer of Boric Acid from Cattle Food 



to Oow's Milk. (Durham County Council, Ed. Com., Offer ton 

 BuL, 3, 21-4; abs. Dair, 21, 1909, N. 248, 217). E. S. R., 

 XXI, Dec. 1909. 



This experiment was undertaken because boric acid is often 

 used to prevent Indian cotton-seed cake from becoming moldy. 

 Boric acid appeared in the milk as soon as cows were fed daily 

 7 4 Ib. of a meal which contained 5 per cent of boric acid. About 

 one-fiftieth of the boric acid appeared in the milk. When the 

 meal contained i per cent of boric acid about one-seventieth ap- 

 peared in the milk. 



" As milk needs r / 4 P er cent boric acid to produce any useful 

 preservative influence, there seems no difficulty in distinguishing 

 between milk preserved with boric acid and milk contaminated by 

 the use of foods containing boric acid. If milk be found to con- 

 tain more than 0,1 per cent boric acid the milk has probably been 

 deliberately preserved with some boric preservative, but if less than 

 0,01 pes cent boric acid be found in the milk, the source of that 

 small amount of boric acid is to be looked for in the food of 

 the cow. " 



The Handling of Milk in the Tropics. - The Tropical Life, 



Vol. VI, p. 98. London, May 1910. 



The most recent, and probably the most valuable method of 

 preserving milk is that known as Buddeization, an account of which 

 appeared in the Lancet of December 14 1907. Put very briefly, 

 the process consists in cooling (which however, must not be carried 

 to far, because, in excess, it destroys the natural antibacterial qua- 

 lities of the milk), heating to 50 C., centrifugating, again heating in 

 a vat, and adding peroxide of hydrogen. This acts, both in virtue 

 of its own strong germicidal power, and still more owing to the 

 fact that the milk catalase (an enzyme of the living cell) is able 

 to decompose the hydrogen peroxide, setting free nascent oxygen, 



