CHEMISTKY. 641 



ether was found unsatisfactory by the author. The usual time of extraction was 

 insufficient to remove all the fat. The Gerber te;»t is considered preferable to all 

 others if made properly. 



The improved Gerber method of determining- fat in cheese, P. Wieske 

 (Molk. Ztg., 18 (1904), No. 24, p. 556). — The article describes Siegfeld's modification 

 of the Gerber method for the determination of fat in cheese, consisting in dissolving 

 the cheese in hot acid | 80° ( '. i and adding amy] alcohol alter the solution lias cooled 

 to about 60° C. The author states that the modified method gives equally satisfac- 

 tory results in the ease of full-cream cheese, Swiss, Tilsit, and hard skim-milk 

 cheese. — f. w. woll. 



The identification of cocoanut oil in butter fat, F. Wiedmann i Molk. Ztg., 18 

 (1904), No. 29, pp. 681-688). — The author recommends the following methods for 

 determination of adulterations of butter fat with cocoanul oil and other foreign hits: 

 Reichert-Meissl number, Polenske tesl i E. S. li., 15, p. 850), and the melting point 

 of the insoluble fatty acids. — f. w. woll. 



The identification of cocoanut fat in butter, A. Skoin (Arch. Pharm., 242 

 (1904), No. 6, pp. 441-450). — Studies of methods of estimating cocoanut fat. 



Studies on the browning 1 and foaming of natural butter and margarine 

 when heated, P. Pollatschek (Chem. Rev. Fett-u. Harz-Ind., // (1904), PP- 

 28; abs. in Ztschr. Dntersuch. Nahr. u. Genussmil., 8 (1904), No. 4, p. 248). — In con 

 nection with studies of renovated butter the author was led to study the reasons for 

 the foaming which is observed when butter and oleomargarine are heated, and came 

 to the conclusion that it is due to the presence of minute quantities of soaps. The 

 browning of natural butter, he concluded, could not be attributed alone to its 

 lecithin content. 



Browned butter contains a fine precipitate which is of a brown color, and the fat 

 itself is also a dark brown. In the case of oleomargarine, the addition of egg white 

 ami also yolk with milk sugar gives a brown sediment when the fat is heated. The 

 fat itself remains yellow or is only slightly darkened. When egg oil and lecithin 

 are added in small quantities the fat becomes slightly brown, but a considerable 

 amount of lecithin, 4.5 per cent, is required to cause as dark a color as is noted when 

 natural butter is browned. 



The conclusion was reached, therefore, that lecithin is not the sole cause of the 

 browning of natural butter as in cookery. 



Concerning the comparative viscosity of culinary fats and oils, M. Pleiss- 

 ner (Arch. Pharm., 242 (1904), No. /, pp. 24-81, fig. 1, dgms. 2). — Experimental 

 data are reported and discussed with special reference to the use of this factor as a 

 means of detecting adulteration. 



A synthesis of fat through the reversible action of a fat-splitting enzym, 

 A. E.Taylor (Univ. California Pubs., Path., I, 3, p. 83; abs. in Zentbl. Physiol., 18 

 (ly04), No. 17, p. 524). — Using lipase from castor-oil beans, the author was able to 

 produce olein from glycerin and oleic acid. No glycerid could be formed, however-, 

 from acetic, butyric, palmitic, or stearic acid, nor could a triglycerid be formed using 

 mannit or dulcit instead of glycerin. 



The heat of combustion of a number of organic compounds, E. Fischer and 

 F. Wrede (Sitzber. A'. Preuss. Akad. Wiss. [Berlin], Phys.-Math. Kl., 1904, Apr., p. 

 687; abs. in Zentbl. Physiol., 18 (1904), No. 18, pp. 874, 375).— Using a modified form 

 of the Berthelol bomb, the author determined the heat of combustion of a number 

 of compounds of especial interest from the standpoint of physiological chemistry and 

 studied the relation between heat of combustion and chemical structure. The con- 

 clusion is especially interesting that the formation of a polypeptid from the corre- 

 sponding amido acid (calculated as a solid) is accompanied by the absorption of 

 about 4.5 calories for each anhvdrid condensation. 



