178 EXPERIMENT STATION KECOED. 



London milk, H. D. Richmond and C. Revis {Jour. Roy. Inst. Pub. Health, 

 15 (1901), No. 5, pp. 268-272). — The authors question the accuracy of the ana- 

 lytical data reported in the above article as well as the soundness of the con- 

 clusions reached. 



Bacterial content of milk, Szasz {Abs. in Ztschr. Fleisch u. MUchhyg., 17 

 (1007), Xo. 10. p. 3.53). — The author examined 150 samples of market milk in 

 Budapest, finding an average l)acterial content of 1,563.000 bacteria per cubic 

 centimeter. The range was from 18.000.000 to 52,800. 



Homogenization of milk, C. Istaz and G. Van Soest (Rev. Gen. Lait, 6 

 (1907), Xo. 11, pp. 2Jjl-2.'i8). — The literature of this subject Is briefly reviewed 

 and experiments are reported, the authors concluding that the agidity of milk is 

 not increased by homogenization, that the chemical composition is not sensibly 

 altered, and that if foreign fats have been added to market milk in this way the 

 fraud has at least not been practiced on the samples examined by them. No real 

 physiological advantages from homogenization have as yet been demonstrated. 



Preservatives in milk, H. D. Richmond and E. H. Miller (Analyst, 32 

 (1907), Xo. 37-'i, pp. l-i-'f-lo'f). — The authors believe that the acidity of milk can 

 be expressed with fair accuracy as a function of time and temperature. Be- 

 tween 15 and 35° C. the effect of temperature is quite regular, each rise of 10° 

 Increasing the rate of development of acid 2.075 times. 



The authors have studied the effect of various so-called preservatives upon 

 the souring of milk. The following substances apparently hastened souring: 

 Sodium fluorid, acid-potassium fluorid, sodium sulphite, resorcin, and phloro- 

 glucin. The following had no appreciable preservative action : Phthalic acid, 

 abrastol, sodium /3-naphthol, sulphonate, and cyllin. The following had an 

 appreciable preservative effect : Sodium benzoate, potassium benzoate. ^-naph- 

 tbol, salicylic acid, potassium metabisulphite, and borates. 



In the authors' experiments milk kept at 30° C. became sour enough to curdle 

 on boiling in 17 hours. The addition of 0.1 per cent of the following preserva- 

 tives delayed the time of souring the number of hours indicated after each^ 

 Boric acid 10, benzoic acid 51, salicylic acid 7J. /3-naphthol 4i, and potassium 

 metabisulphite 21. " When it is considered that the same effect can be attained 

 by cooling the milk down a few degi'ees, at a cost which certainly does not 

 exceed that of the preservative, it is evident that there is no justification for 

 the use of preservatives in milk." 



Notes are given on the detection and estimation of benzoates, /3-naphthol, and 

 boric acid. 



Dairy inspection in Ireland, P. .J. How.\rd (Jour. Roy. Inst. Pub. Health, 

 15 (1907), No. 5, pp. 273-278). — There is, according to the author, practically 

 no dairy inspection in Ireland. The need of inspection is therefore discussed in 

 this article and a simple system is briefiy outlined. 



The pasteurization and the inspection of creamery and cheese factory by- 

 products, E. H. Fakrington and E. G. Hastings (Wisconsin Sta. Bui. 148, pp. 

 17, flys. 3). — Methods of pasteurizing skim milk, buttermilk, and whey are 

 brieflj- outlined and several arrangements for this purpose are described and 

 illustrated. Suggestions are made concerning the removal of the foam from hot 

 skim milk, and the feeding value of pasteurized skim milk is discussed. It was 

 found experimentally that in pasteurizing skim milk by forcing steam into it 

 about 10 per cent of water was added to the milk. Buttermilk in amounts not 

 to exceed 5 per cent may be added to sweet skim niillc and pasteurized witliout 

 the mixture's curdling. 



Various tests for the detection of jiasteurized milk and whey are described. 

 The potassium iodid-starch test is recommended for general use. 



