AGRICULTURAL CHEMISTRY AGROTECHNY. 309 



Eefraction and specific gravity of the calcium chlorid milk serum, C. Mai 

 .•iml S. KoTHKNFUSSER (MUchw. Zenfbl., 6 (liJlO), Ao. '/, /;/;. I'f6-15.'i). — A po- 

 U'luical article, continuing previous discussions (E. S. R., 20, p. 706; 21, p. 11; 

 22, p. 511). 



The relation of the acidity to the catalytic power of fresh milk, J. Sarthou 

 (Jour. /'Jianii. rt Chiiii., 7. .sf r., / ( 1!)10), Ao. 8, pp. 387 -3!) 3) .—The author draws 

 .Mttention to the fact that no relation exists between the catalytic activity and 

 tljc amount of acid present in the milk. Estimating the catalytic power, how- 

 ever, will determine the degree of freshness of the milk. 



Diastases in milk (peroxidases), E. Nicolas {Abs. in Chem. Ztg., 34 {1910). 

 Ao. 21K II. .i'ii>). — The author discusses Bordas and Touplain's work (E. S. R., 

 21. p. 475). which attributes the peroxidase reaction in milk to colloidal casein, 

 and states that if the casein of the milk is removed with acetic acid the result- 

 ing (filtered) serum will decomiiose hydrogen dioxid and give the characteristic 

 reaction with guaiacol. The coloration becomes even more intense if the 

 colloids are removed from the milk by magnesium sulphate or sodium chlorid 

 at a temperature of from 37° to -10° C. 



If to the lactose serum from raw milk (originally treated with acetic acid) 

 from 2 to 3 volumes of alcohol are added, a precipitate is obtained which is 

 soluble in acetic acid and which also contains the active substance. This pre- 

 cipitate when washed with alcohol, rubbed up and treated with distilled water 

 or slightly acidified water, gives up the peroxidase substance to the water and 

 in which the characteristic reactions can be obtained. The author expresses 

 the opinion that a soluble product exists in milk which possesses the peroxidase 

 activity. 



Milk ferments, J, Meyer (Arl). K. Gsndhtsamt., 3'/ {1910), No. 1, pp. 115- 

 121). — From the results it appears in contradistinction to those obtained by 

 Bordas and Touplain (E. S. R., 21, p. 475) that the sediment and cream 

 layer from a filtered milk which has been heated for a sutticient length of time 

 will not decompose hydrogen peroxid nor give a blue coloration with para- 

 phenylendiamin. When the sediment liberates hydrogen peroxid this is prob- 

 ably due to the dirt particles contained therein, which sometimes are capable 

 of acting as catalysts. 



Tests with raw milk casein showed that while this substance was capable of 

 decomposing hydrogen peroxid it did not bring about an oxidation of the 

 paraphenylendiamin with hydrogen peroxid. Heated casein also did not liberate 

 oxygen, nor did it oxidize paraphenylendiamin in the presence of hydrogen 

 peroxid. Milk serum (obtained by filtering through a coUodium ultra-filter) 

 when rubbed up with raw casein did not give the characteristic reaction. 

 Attempts to reactivate boiled milk with pumice stone or platin sole showed that 

 the hitter brought about an active reaction almost immediately, while i)umice 

 stone did this slowly. 



Examination of condensed milk {Pharm. Post., 1/3 {1910), No. 2.'/, pp. 235, 

 236). — A method employed by the treasury department (technical control) at 

 Vienna is given. 



Condensed milks usually contain sucrose (R) in addition to lactose (M) and 

 possibly fluctuating amounts of invert sugar (I), so that G (total sugar) =R + 

 M+I. The total sugar is determined after inversion with Fehling's solution 

 and the result calculated as cane sugar. In a second sample the cine sugar 

 and the invert sugar are fermented with press yeast and the remaining milk 

 sugar determined with Fehling's solution and the findings reported as cane 

 sugar. The difference (G— M) gives the cane sugar content. 



