1002 EXPERIMENT STATION RECORD. 



Preservation of milk by hydrogen peroxid, A. Renard {Ah,t. in Jovr. Soc. 

 C'lti'iii. IikI., ;.-*.) {I'JO-'i), .\<i. ..', J). 7.}). — ( >l)servati(>iis are given on the rate of decom- 

 position of hydrogen peroxid in milk. A (juantity not exceeding 2 per cent of a 12- 

 volume solution was completely decomposed in from 6 to 8 hours. With the addi- 

 tion of 5 per cent of a 12-volume .solution the decomi)Osition was not complete after 

 several days. 



While a small iiuantity of liydrogcn peroxid does not sterilize the milk, the keep- 

 ing qualities are much imj)roved. The milk i)reserved with 1, 2, and .3 per cent of 

 a 12-volume solution remained sweet for 24, 20, and 32 hours, respectively, at 20° C, 

 while milk not preserved soured in 13 hours. It is considered hest to add the 

 hydrogen jjcroxid immediately after milking and keep the milk in a cool place for 

 fi to 8 hours until the liN-drogi-ii j)ei'oxid is completely decomposed. 



The presence of a lipase in milk, C. Gillet {Jour. Physiol, el ruth, flcn., 1903, 

 No. S; aha.inRer. Gm. Lait, 3 {1903), No. 4, IW- 89,90). — The investigations were 

 made w'ith human milk obtained with every aseptic precaution. Only exceptionally 

 was the milk sterile. StajJn/Iococcus pyogenes albus was almost constantly present 

 and S. ]>yogenes aureus occasionally found. Both sterile and contaminated milk 

 caused a decomposition of monoljutyrin. This action was not increased by the 

 development of bacteria in the milk, but was destroyed by a high degree of acidity. 



Pure cultures of the bacteria found in the milk were lot able to decompose the 

 glycerid. The activity of the ferment was diminished but not prevented by the 

 addition of sodium tluorid or chloroform. The ferment was not destroyed by the 

 coagulation of the milk. It resisted temperatures to 60-65° C, and was found to 

 have no action on other glycerids than monobutyrin, and ought therefore to be 

 designated merely a monobutyrinase rather than a lipase. The monobutyrinase 

 was found also in the milk of the cow, ass, and goat. 



It is believed that a number of enzyms exist in milk, anaerobic oxydase, mono- 

 butyrinase, and amylase being mentioned. It is considered that no satisfactory 

 explanation concerning the physiological role of these ferments has yet been offered. 



The oxidizing ferment in milk, L. M. Spolverini {Her. Ilyg. d Med. Iiifantlles, 

 3 {1904), No. 2, pp- 113-155). — The author discusses oxidizing ferments in general 

 and reports extended investigations on the oxidizing ferment in the milk of the cow 

 and goat, and in human milk. A distinction is made between the direct oxidizing 

 ferments, or the oxydases which have the power of utilizing directly atmospheric 

 oxygen, and the indirect oxidizing ferments, or anaerobic oxydases which are incapa- 

 ble of oxidizing substances in the presence of atmosi^heric oxygen alone, but which 

 require an intermediate substance rich in oxygen, as for instance, hydrogen peroxid. 

 Home of the conclusions drawn from the results as a whole are noted below. 



lender normal conditions an;erobic oxydase is constantly present in considerable 

 quantities in the milk of cows and goats, in which the ferment is found uniformly 

 diffused throughout the milk serum and is not in combination with cellular elements. 



Human colostral milk always produces a noticeable oxidizing action, due to the 

 presence of organized elements in the milk. While the amount of the anaerobic 

 oxydase in human milk varied considerably in the 57 cases under observation, its 

 complete absence was very rare. In human milk containing colostral corpuscles the 

 f)xydase was l)elieved to exist mainly within the organized elements, while in other 

 milk it was found to be diffused throughf)ut the serum. 



The ana'robic oxydase of the milk of cows and goats Mas believed to be a product 

 of normal elimination. This was thought to be only exceptionally the case in human 

 milk. By modifying the food of a goat, as by feeding the oxidizing ferment, the 

 amount of the oxydase in the milk and in the urine was made to increase or decrease. 

 The characteristic reaction of anaerobic oxydase was thought to be due to two special 

 ferments, one decomposing the hydrogen peroxid, and the other fixing the oxygen. 



