700 EXPERIMENT STATION RECORD. 



end of 24 hours and in no instance was it present after 3 days. A diminution in 

 the amount present was recognized as early as the sixth hour. In the proportion of 



1:10,000 and 1:20,000 its disappearance was also rapid and in most instances was 

 complete at the end of ."> days. In the proportion of L: 1,000 the disappearance was 

 very slow*, scarcely any change being observed up to the tenth day, although by the 

 twenty-fifth day it had partially disappeared. In all instances the disappearance of 

 the formaldehyde was more rapid at high than at low temperatures. 



"The fact that samples of market milk show unusually good keeping qualities and 

 yet apparently do not contain formaldehyde, should at once raise suspicion that 

 these samples may have had formaldehyde added to them, and that in time the 

 formaldehyde has disappeared from such milk." 



The suitability of hydrogen peroxid for the sterilization of milk, P. Goedan 

 (Centbl. Ball. u. Par., 2. Abt., 13 {1904), No. 22-23, pp. 716-728).— Buckle's method 

 of sterilizing milk (E. S. R., 14, p. 1009), by the addition of hydrogen peroxid com- 

 bined with heating the milk was tested. The results showed that in the small quan- 

 tities recommended by Budde the hydrogen peroxid was entirely incapable of 

 sterilizing the milk, and that not until 3 times the quantity recommended was added 

 were all the bacteria destroyed. 



Small quantities of hydrogen peroxid had no appreciable influence on the taste of 

 the milk. Larger quantities caused a biting, unpleasant taste, and in quantities of 

 0.1 per cent it rendered the milk unfit for human consumption. Typhoid bacilli and 

 spores of Bacillus subtilis added to milk were not destroyed by the Budde method 

 (0.35 cc. of hydrogen peroxid per liter of milk with heating to 50° C. ), although in 

 quantities of 0.07 per cent or more positive results were obtained. 



Obtaining raw sterile milk, H. de Waele, E. Sugg, and A. J. J. Vandevelde 

 (Centbl. Bali. u. Par.. .'. Abt., 13 (1904), No. 1-3, pp. 30-35).— Raw sterile milk 

 adapted for use as a culture medium was obtained by treating milk with 0.3 to 0.4 

 per cent of hydrogen peroxid, allowing the sample to stand for 3 to 8 days, and then 

 removing the undecomposed hydrogen peroxid by the addition to each 100 cc. of 

 milk of 0.1 to 0.2 cc. of defibrinated laked blood sterilized by the addition of 1 per 

 cent of formalin. A bibliography is appended. 



On the proteolytic enzyms of milk, A. J. J. Vandevelde, H. de Waele, 

 and E. Sugg (Beitr. Chem. Physiol, u. Path., 5 (1904), No. 11-12, pp. 571-581).— 

 Sterilization of milk was secured by the use of hydrogen peroxid, which was not 

 believed to affect the enzyms present. In this way the authors demonstrated the 

 presence of a proteolytic enzym in milk and showed that the action of this enzym 

 was increased by an alkaline reaction and by an increase in temperature. A slight 

 proteolytic action was attributed to the hydrogen peroxid itself, but this was easily 

 distingushed from that of the enzym. 



The occurrence of changes in the composition of milk sterilized with hydrogen 

 peroxid was also demonstrated by means of serum tests with guinea pigs, and further 

 by the time required for coagulation with rennet. Under the conditions of one 

 series of the rennet tests fresh milk became coagulated in 1 hour and 45 minutes. 

 This time was shortened to 50 minutes by the addition of hydrogen peroxid. in 

 samples so preserved the time required for coagulation increased with the age of the 

 sample, until at the end of 78 days it was 3 hours and 10 minutes. Some of the lit- 

 erature of the subject is briefly reviewed. 



On the isolation of fermentative enzyms from cows' milk, J. Stoki.asa 

 et al. (Ztschr. Lanctw. Versuchw. Oesterr., 7 (1904), No. 11, pp. 755-774, fig- 1 )-~ 

 Fresh milk was treated with alcohol and ether and the resulting precipitate or crude 

 enzym was collected by filtration through linen cloth and dried to remove all traces 

 of the precipitants. Sterile lactose solutions were fermented with the enzym thus 

 obtained under conditions excluding bacterial action, and the decomposition products 



