503 EXPERIMENT STATION RECORD. [Vol. 3« 



The determination of volatile fatty acids according to the method of 

 Duclaux, A. VoiTKEVicH (A. Wojtkiewicz) {Vtestnik Balct. Agron. Sta. V. K. 

 Ferretn, No. 21 (191^), pp. 180-188). — The method is described in detail, and 

 analytical data obtained by its application to a mixture of acetic, propionic, 

 and butyric acids submitted. 



In a comparative study of the method and the distillation of pure acids 

 results not differing more than 5 per cent from each other were obtained. The 

 variation is attributed to differences in the conditions of the distillations. The 

 method is deemed to yield accurate and trustworthy results. 



Estimation of sugar in meat products, particularly extracts, W. B, Smith 

 {Jour. Indus, and Engin. Chem., 8 0916), No. 11, pp. i024-i 027). —Slightly 

 modified methods in which mercuric acetate and picric acid are used as protein 

 precipitants are outlined. 



The experimental data submitted show that the clarification of meat extract 

 solutions for the estimation of sugar by Fehling's solution is best accomplished 

 by using an excess of picric and phosphotungstic acids, followed by a very 

 small quantity of hydrochloric acid. With the proper precautions reducing 

 sugar may be determined witliin 0.1 or 0.2 per cent in the presence of sucrose. 

 The total reducing sugar may be determined within 0.1 per cent. 



The determination and distribution of moisture in bread, Hannah L. 

 Wessling {Jour. Indus, and Engin. Chem., 8 {1916), No. 11, pp. 1021, 1022, 

 figs. 2). — For the determination of moisture in bread the author uses one-half 

 or one-fourth of a loaf, depending upon the character of the crust, and then 

 proceeds as follows : 



A suitable portion of the bread is weighed as quiclily as possible in a tared 

 dish on a torsion balance, and then carefully heated at a temperature not 

 exceeding 60° C. until practically dry. The dry bread is allowed to stand 

 exposed at room temperature for a few hours in order that its moisture content 

 may come into equilibrium with that of the air, and the loss in moisture to this 

 point is then determined. The air-dried sample is immediately ground to a 

 fine meal and the moisture determined in a 2-gm. sample in the vacuum oven 

 at the temperature of boiling water. From the percentage of moisture obtained 

 in this subsample the total percentage of moisture in the bread is calculated 

 by adding this to the amount lost on heating at 60°. This procedure is prac- 

 tically the same as that previously described.^ 



The results obtained indicate that there is no appreciable difference in 

 moisture content in slices of bread taken at a reasonable distance from the end 

 of the loaf, or in the crumb of any individual slice taken at a reasonable 

 distance from the crust. A great difference, however, was observed between 

 the moisture obtained in the whole bread (as determined on one-half or one- 

 fourth of a loaf) and that in either the crust or crumb taken separately or in 

 one entire slice. In reporting the moisture content of bread it is necessary, 

 therefore, to state what portion of the bread was used as well as how the 

 moisture was determined. 



Microscopical examination of chocolates and cocoas. — Determination of 

 shell material in seeds, E. Collin and L. Gobert {Ann. Falsi/., 9 (.1916), No. 

 92-93, pp. 191-202, figs. 8). — The authors discuss the materials present in 

 chocolate and cocoa which might be considered as adulterants and outline in 

 detail a procedure for microscopical examination. Formulas for calculating 

 the quantity of such foreign material are submitted, together with analytical 

 data obtained from the examination of six samples of chocolate and i?even of 

 cocoa. Since the presence of such material can hardly be avoided or prevented 

 in the finished product, it is suggested that in order to secure uniformity the 



*Arb. K. Gsndhtsamt., 48 (1915), No. 4, pp. 605, 606. 



