D a IKY FABMING DAIB1 [NG. 75 



peroxid in the proportion of 0.18:1,000 and a temperature of 15 or 0.35 : 1,000 al 

 room temperature. 



■ Tubercle bacilli were also added to Bterilized milk, which was then treated with 

 hydrogen peroxid in the proportion of 0.35:1,000. Inoculation experiments with 

 guinea pigs gave negative results as regards infection. It was concluded as the resull 

 of 2 series of experiments thai both bacteria and enzyme in milk are capable of 

 decomposing hydrogen peroxid. 



Treatmenl with hydrogen peroxid was found to lengthen materially the time 

 required for coagulation of milk with rennet extract , and also to bring about certain 

 changes in the character of the curd. In artificial digestion experiments the pepsin- 

 hydrochloric-acid solution Beemed to acl more rapidly and energetically on the sam- 

 ples treated with hydrogen peroxid than on raw milk. The results of the digestion 

 ami coagulation experiments are therefore considered as offering no objection to the 

 use of hydrogen peroxid in milk. Aside from its possible use in infant feeding, milk 

 preserved with hydrogen peroxid is believed to he well suited to use in the army 



and navy and in the Tropics. 



In the practical application of hydrogen peroxid to the preservation of milk, it is 



pointed out that every precaution should be taken to prevent contamination of milk 

 during milking, that milk should be treated immediately after milking before a 

 multiplication of bacteria has taken place, and that the 30 per cent hydrogen-peroxid 



solution can be used to avoid dilution of milk. 



On the question of the preservation of milk with formaldehyde, especially 

 for the purpose of infant feeding-, L. Schaps (Ztschr. Hyg. ". Tnfectionskrank., 50 

 (190;~>). No. ?, pp. 247-S64, figs. 7). -Some of the literature of this subject is briefly 

 reviewed. 



Experiments are reported which show the Length of time that formalin in the 

 proportions of l:10,000and 1 : 5,000 delays the souring of milk at room and incu- 

 bator temperatures. The author claims that formalin in the proportion of 1:10,000 

 renders the milk objectionable on account of taste and that in the proportion of 

 1:40,000 it is still distinctly recognizable, which is contrary to the statement of 

 Behring that milk treated with formalin in the proportion of 1:4,000 could not be 

 distinguished from untreated milk. 



Samples of raw milk and milk preserved with formalin in the proportion of 

 1:10,000 and 1:5,000 were inoculated with Staphylococcus pyogenes albus and kept 

 at room temperature for L2 hours. Plate cultures were then made and examined 

 after remaining 24, 48, and ~'l hours in the incuhator. When examined at the end 

 of 24 hours many of the plates showed colonies only in the case of milk not treated 

 with formalin, but when examined at a later period it was apparent that formalin 

 had not destroyed the staphylococci. 



Formalin checked the development of the lactic-acid bacteria to a much greater 



extent than that of the staphylococci. As determined by inoculation experiments 

 with guinea pigs, formalin in the amounts ahove mentioned failed to destroy tubercle 

 bacilli added to raw and sterilized milk. 



The history and post-mortem findings in the case of an infant which had been led 

 milk preserved with formalin in the proportion of 1:10,000 are reported, but the 



data warranted no positive conclusion as to the influence of formalin. On tin- evi- 

 dence so far obtained the author objects to the use of formalin as well as to that of 

 other preservatives in milk. 



Milk preserved with formalin and the relation of formalin to certain spe- 

 cies of bacteria, 1". Sommkrfeld [Ztschr. Hyg. ". Tnfectionskrank.,60 (1906), A". /. 

 i>/>. tSS-164). — The author found that formalin added to fresh milk in the proportion 

 of 1:5,000 or 1:10,000 was capable of hindering to a marked extent the development 

 of bacteria. 



