DAIRY FARMING — DAIRYING. 193 



In neither ease was sugar present in the urine hefore parturition, hut it was present 

 in large quantities, mainly in the form of glucose, after parturition. A slight amount 

 of lactose found in the urine was attributed to the incomplete removal of the gland- 

 ular tissue. The author therefore concludes that normally the glucose is transformed 

 into lactose in the mammary gland. 



On the origin of lactose, C. Porcuer and Commaxdeur (Compt. Rend. Acad. 

 Sri. Paris, 138 (1904), No. 14, pp. 862-865).— A study of the urine of a pregnant 

 woman suffering with diabetes confirmed the author's conclusions, noted above, that 

 normally lactose is produced from glucose in the mammary gland. 



On the origin of lactose, ('. Porcher (Compt. Rend. Arm!. Sri. Paris, 138 (1904), 

 No. IS, pp. 924-926). — Observations were made on cows affected with milk fever, the 

 results of which, along with those obtained in previous studies, are believed to 

 establish thoroughly the role of the mammary gland in forming milk sugar from 

 glucose brought to it from the blood. 



On the decrease in the citric-acid content of milk due to heating, (I. Ober- 

 maier (Arch. Hyg.,50 (1904), No. /, pp. 52-65). — The fact that symptoms of infantile 

 scurvy often appear in infants fed sterilized milk, and the fact also that such symp- 

 toms tend to disappear by the feeding of uncooked milk or the administration of 

 fruit juices containing citric acid, led the author to make determinations of citric acid 

 in milk subjected to heating at different temperatures for varying lengths of time. 



In general, heating was found to produce a notable diminution in the percentage 

 of citric acid which, according to different observers, is normally from 0.18 to 0.25 

 per cent. Heating for 10 minutes on an open fire caused a diminution of about 15 

 per cent of the total amount present. The explanation is offered for this change 

 thai the citric acid exists normally in milk in the form of an acid salt, calcium bici- 

 trate, and is transformed by oxidation during heating into calcium tricitrate, which 

 is only slightly soluble. Heating at 80° C. produced a much smaller change in the 

 content of citric acid, and in this respect pasteurization at that temperature is better 

 than sterilization at 100°. 



Influence of aeration on lactic fermentation, C. Barthel (Rev. Gen. Lait, 3 

 (1904), No. 13, [>i>. 294-301). — Experimental work is reported, from which the con- 

 clusions are drawn that aeration retards fermentation in milk due to bacteria belonging 

 to the lactic-acid group, and that the retardation caused by aeration is still further 

 increased by the lowering of the temperature. 



Experimental investigations on the preservation of milk, C. Nicolle and 

 E. Ducloux (Rev. Hug. el Police Sanit., 26 (1904), No. 2; abs. in Bui. Inst. Pasteur, 2 

 (1904), No. 11, p. 504).— Milk kept at 5° C. for 24 hours showed at the end of that 

 time 10,800 bacteria per cubic centimeter, while milk kept at 14° showed 5,820,000 

 bacteria, showing the benefit of refrigeration in reducing the number of bacteria. 



Tests were also made of hydrogen peroxid as a means of preserving milk. Hydro- 

 gen peroxid was added to milk to the extent of 1 to 2 per cent, and the samples 

 were then kept at temperatures of 15, 22, and 34°. In the samples treated with 

 hydrogen peroxid the number of bacteria diminished during the first 10 hours, fol- 

 lowing which the number of bacteria gradually increased, but did not in any case 

 equal the number in the control samples. No trace of the antiseptic was found in 

 the milk after several hours. 



While the use of hydrogen peroxid has an advantage over pasteurization in not 

 altering the constitution of the milk, it does not destroy the pathogenic bacteria. 



On pasteurized milk, N. Swellengrebel ( Gentbl. Bakt. u. Par., 2. Abt., 12 

 (1904); No. 11-16, pp. 440-448). — Bacteriological examinations of pasteurized milk 

 sold in hermetically sealed bottles in Amsterdam showed a wide variation in the 

 bacterial content. The lowest number per cubic centimeter found was 290, and the 

 highest 49,875. Other causes than the temperature of pasteurization were believed 

 to influence these results. 



