REVIEW — TROPICAL MEDICINE, ETC. 131 



The B. enteritidis sporogenes is of particular importance, as it does not multiply in the Milk- 

 milk, and can therefore be accepted as an indication of the original pollution of the milk. omtinncd 



Streptococci should not be present, and show disease of teats or inflammatory 

 conditions of milk glands. They are instrumental in causing sore throats, and give a 

 standard of sanitary requirement for the country and for the town. 



Eevis" has also a paper on the detection of added water to milk, and after citing 

 the three ways in which the defendant in a case may prove the contrary, none of which 

 are very satisfactory, he states that : — • 



Prom a careful study of the records of analyses of genuine abnormal milks, of which a great number will be 

 found scattered throughout the literature of milk, two general hypotheses may be formed, viz. : — 



1. When genuine milk is deficient in non-fatty solids, the deficiency is due entirely to an abnormally low 

 percentage of milk sugar, the proteids and ash being present in their normal amounts. 



2. When a genuine milk shows an unusally high percentage of non-fatty solids, the increase is due almost 

 entirely to an abnormally high percentage of the proteids, the sugar and ash either remaining normal or perhaps 

 slightly increasing also. 



With the latter hypothesis we are not here concerned. The former, however, is of immense importance, as it 

 allows of a simple means of dMereutiating, among milks of low non-fatty solids, between a deficiency duo to 

 natural causes and causes distinctly fraudulent, such as the addition of water. Stated in a concise form, we may 

 put it thus : — 



If in the case of a milk in which the percentage of non-fatty solids is below 8' 5 per cent., an estimation of 

 the sugar gives a figure considerably less than 13/24 of the estimated non-fatty solids, and such that the total sum 

 of non-fatty solids could only be present if the sugar were present with a normal amount of proteids and ash, we 

 have very strong evidence that the deficiency of milk solid is due to natural causes only. If, on the other hand, 

 the sugar figure approximates closely to 13/24 of the estimated non-fatty solids, the evidence is just as strong that 

 the deficiency is due to fraudulent adulteration with water. The simple addition, therefore, of a sugar 

 determination to the usual estimation of fat and total solids, furnishes the analyst with evidence of the most 

 useful kind in deciding on the cause of a deficiency of non-fatty solids in a sample of milk. 



The polarimetrie estimation of sugar in milk is simple, rapid and exact, and there can be no possible objection 

 to it. The only objection of any weight to the whole procedure that can be brought, is the difficulty of putting 

 samples rapidly enough in the analyst's hands before lactic fermentation has destroyed an appreciable amount of 

 sugar. Such a difficulty could be easily surmounted by the exercise of a little administrative capacity. 



An article by Musgrave and Richmond- on infant feeding and its influence upon 

 infant mortality in the Philippine Islands deals amongst other things with milk ; human 

 milk, goat's milk, cow's milk, caraboa's milk and various kinds of sterilised and preserved 

 milks being considered. The paper has chiefly a local interest, but as some of the brands 

 of milk examined have evidently a world-wide distribution and are to be found in the 

 Sudan, reference to their analyses may be useful, while the rules for infant feeding in 

 the Tropics are to be commended. 



Passing now to methods for preserving milk, the most recent, and probably most 

 valuable, method is that of Buddeization — an account of which appears in the Lancet, of 

 December Idth, 1907. Put very briefly, it consists in cooling, which, however, must not 

 be carried too far, because in excess it destroys the natural anti-bacterial qualities of 

 the milk, heating to 50°C., centrifuging, 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, which has a still greater 

 bactericidal action. 50'^ C. is found to be optimum temperature for this action. There is a 

 stirrer in the vat, and when the sterilisation is complete the milk is either cooled first 

 and then bottled, or run into sterile bottles and then cooled. As the presence of the 

 catalase is not absolutely uniform, it is best to add so much peroxide of hydrogen that 

 there is certain to be a trace left at the end of the process. Then immediately before 

 bottling a few drops of catalase solution are added. 



Milk, after having been subjected to the foregoing treatment, possessed the following 

 qualities. None of the component parts of raw milk were in any way altered. The milk 

 was practically sterile, and most specially so in regard to the specific pathogenic micro- 

 organisms. The milk was able to be kept considerably longer than ordinary milk, but 

 notwithstanding this fact it should, of course, like all milk, be consumed as fresh as 

 possible. The milk was absolutely free from foreign substances. As for the milk enzymes, 

 the tryptic and peptic proteases and the lipases were unimpaired. The oxydases were 



1 Eevis, C. (.January, 1907), "The Detection of Added Water in Milk." Jaurnal of the Royal Institute 

 of Public Health, Vol. XV. 



'^ Musgrave, W. E., and Richmond, H. T. (August, 1907), " Infant Feeding and its Influence upon Infant 

 Mortality in the Philippine Islands." I'hilippine Journal of Science, Vol. II., B. 



