DAIRY FARMIlSrG DAIRYING. 387 



The composition of colostrum, W. F. Suthekst (Clieui. Neivs, 86 {1902), No. 

 :?JJ.)', jiji. 1, ..', (Igiii. 1). — Colostrum was obtained from a Shorthorn cow twice a day 

 for 10 days, and analyzed, the data l)eing given in detail. Tlie percentages of the 

 different constituents for the first and last inilkings, respectively, "were as follows: 

 Total solids, 22.878 and 16.058; asli, 1.034 and 0.814; fat, 2. 302 and 4. 796; lactose, 2.742 

 and 4.874; total albuminoids, 12.236 and 3.242; casein, 4.858 and 2.250; globulin, 5.321 

 and 0.198, and albumin, 1.454 and 0.562. The specific gravity decreased from 1.068 

 to 1.030. The percentage of globulin decreased very rapidly for the fir.«t 3 inilkings 

 and then remained practically constant. All the other constituents increased or 

 decreased gradually, c(jnilibrium ])eing reached at about the ninth milking. 



Variation in the phosphoric acid in milk during lactation, F. Bokuas and 

 S. DE Raczkoavski {C'ompt. Rend. Acad. Sri. Paris, 135 {1902), No. 5, pp. 302, 303). — 

 Analyses of the milk of 7 cows in different stages of lactation showed a maximum 

 content of phosphoric acid and lecithin at the beginning of lactation and a gradual 

 decrease during the remainder of the period. 



The hygiene of milk, W. Stieger {Die Hygiene der Mitcli. Leipzig: M. Ileinsius 

 Nachfolger, 1902, pp. VIII + 244, p'x- 15, figs, i^,?).— This treats in a general way of 

 the production, handling, and preservation of milk and its products under hygienic 

 conditions. INIethods of testing are described and the feeding of infants is considered 

 at some length. 



The care and handling of milk, 0. F. Hunziker {New York Cornell Sta. Bui. 203, 

 pp. 18, figs. 2, dgiii. 1). — Tlie author discusses the source of bacteria in milk and the 

 means of infection; straining, cooling, and aerating milk; pasteurization and sterili- 

 zation; and storage and transportation. A strainer consisting of a wire gauze and 4 

 layers of cheese cloth has been found the most practical and efficient at the station. 

 Milk kept at 50° F. remained practically unchanged for several days, while milk 

 kept at 98, 80, 70, and 60° curdled at the end of 27, 30, 48, and 72 hours, respec- 

 tively. Many practical suggestions are made throughout the bulletin, which is 

 popular in character. 



Aeration of milk, C. E. Marshall {Michigan Sta. Spec. Bid. 16, pp. 58). — This 

 is a detailed account of studies of the effect of aeration, considered apart from 

 cooling, upon the condition and germ content of milk. Analjses were made of the 

 gases in milk before, during, and after aeration. Experiments were conducted to 

 determine the influence of bacteria and antiseptics upon the interchange of gases 

 between milk and air. The effect of different percentages of carbon dioxid upon 

 the development of bacteria was studied and many other experiments were per- 

 formed. The gas content of the milk was found to (;ontain on an average 81.5 per 

 cent of carbon dioxid and 2.42 per cent of oxygen. Aeration reduced the percentage 

 of carlion dioxid to about 35 and increased the oxygen content to about 20 per cent. 

 The presence of carlxm dioxid in quantities exceeding 33 per cent was found to 

 restrain or prevent bacterial growth. The author draws the following conclusions: 



"Milk undergoes aeration when exposed to air from the time it leaves the milk 

 duct of the cow until it is consumed or made into milk products. 



"This aeration is demonstrated by the reduction in the amount of carlum dioxid 

 and the increase in the amount of oxygen. 



" It has been shown that aerating methods which increase the surface <>f the milk 

 exposed facilitate aeration greatly. 



"Below a certain percentage the elimination of carbon dioxid becomes very 

 difficult. 



"By this interchange of gases between air and milk there is a great oi)portunity 

 offered for the absorption of noxious gases by the milk, unless the interchange takes 

 place in absolutely pure air. 



"Agitation of milk favors the interchange of gases, ])ecause of the increasetl surface 

 exposure. 



