DAIRY FARMING DAIRYING AGROTECIINY. 1077 



Further trials sliowod that this l>acterial activity varied with different cows. 

 It was also found that " coajiuhition and acidity of nnlk do not depend solely 

 upon the bacterial content. They are influenced by natural properties of milk 

 which are soon overshadowed by the metabolic products of bacteria." The 

 authors look ui»on pasteurized or sterilized milk with disfavor, although realiz- 

 ing tiiat at the present time it is a necessity under certain conditions. 



luvestigation of pasteurized milk, O. Galvagno (Centhl. Bakt. [ete.], 2. 

 Abt., 21 (HI08), No. 20-21, pp. 632-().',1 ; ahs. in MUchw. Zrnthh, 5 (1900), No. 1, 

 pp. 35, 36). — The work of other investigators concerning the eHiciency of 

 pasteurizing as a method of destroying bacteria is reviewed. The author made 

 many tests to determine the value of different reagents for testing milk at 

 different temperatures. Arnold's tincture of guaiac method gave an immediate 

 reaction at 25° C. Above or below that temperature the reaction was slower. 

 Schardinger's methylene blue and formalin method is reliable but depends 

 upon many factors besides temperature. The Neisser-Wechsberg method is 

 reliable but requires a much longer time than the Schardinger method. Storch's 

 paraphenylendianiin method gives an immediate reaction in raw milk and in 

 milk heated to 70°, but is negative at temperatures above 79°. Saul's orthol 

 reaction was immediate up to 70°. was retarded at 74°. and negative at 7S°. 

 An iimid potassium iodid solution, to which a drop of hydrogen peroxid was 

 addeil, gave an immediate reaction up to 70°, but at higher temperatures it was 

 retarded, and 2 or more drops of hydrogen peroxid also delayed the reaction. 

 The magnesium sulphate method proved worthless. 



These tests were also used in samples that had been kept G days, raw milk 

 and milk heated to 05° C. being kept on ice and at ordinary room temperature. 

 The preservation of the sample made little difference in the Storch or the amid 

 potassium iodid-hydrogen peroxid methods. The guaiac reaction was retarded. 

 The Saul method reacted as when the sample was fresh up to the fourth day, 

 after which the reaction was slower. The Schardinger method was unaffected 

 inxtil the third day, when the reaction was retarded in both the milks kept on 

 ice, and accelerated with the milk heated at 65° and kept at room temperature. 

 On the fourth day the reaction was accelerated in all cases except with the 

 raw milk kept on ice. On the fifth day the reaction was the same in all cases 

 as on the fourth day, except that the reaction with the milk heated at 05° was 

 accelerated. On the sixth day in ;ill cases the reaction was accelerated. 



On the therapeutic action of fermented milk, C. A. IIehtek {Pop. Sci. Mo., 

 7// (1009), No. 1, pp. 31-Ji2). — A critical discussion on the therapeutic value of 

 fermented milks of various kinds, especially milk fermented by BaciUits biil- 

 gnricus. Many physicians report favorable I'esults from the use of milk that 

 lias undergone lactic-acid fermentation, but little is known as to the nature of 

 its action. By some it is thought that the beneficial results are due to the 

 antiputrefactive action of lactic acid. The reduction of the carbohydrates to 

 lactic acid and a change from a food containing a large ])rotein content will 

 ilwrease the amount of putreH.ible material, but accurate data ;is to any direct 

 action on the part of li. hiih/ariciis is wanting. See also a previous note (E. S. 

 K.. 20, J). 4!»0). 



The effect of hydrogen peroxid on tuberculous milk, A. INIoxvoisin (Iter. 

 (Jen. Lait, 7 il90H), Nos. '/, pp. 73-SO; 5, pp. 97-101). — (}uinea pigs were inocu- 

 lated with milk treated willi hydrogen peroxid by the method of Much and 

 Kfinier (E. S. It., IS, p. 8(!S). The results agreed with those* of Bergmann and 

 Ilnltman, that tuberculous germs are not always killed ]>y sterilizing in this 

 way. I'.acilli taken from yonng cultures were thus destroyed, but from older 

 lullurcs they were more resistant. 



