512 EXPERIMENT STATION RECORD. 



wilt of nltroj;(Mi is iuUk-d (:ifter previous (Ir.viiiK)i •!" '•*"• of fuming' suliiliiiric 

 acid. Tilt' inixdiri' is tlioii poured iuto about 40 cr. of water, nearly neutral- 

 ized witli sodium liydroxid. and made up to 250 cc. Twenty-five cc. is then 

 mixed (witli i)roper precautions) with 25 cc. of Lypobromite solution and tlie 

 dtvoniposition allowed to take place in the Dupre apparatus as modified by the 

 author. To the amount of nitrogen thus found 1.7 per cent must be addttl. as 

 not all of the nitrogen present in the sample is liberated. 



Detection of flour adulteration by the serum diag'nostic method, W. Maci- 

 Nus (Ldndir. Jahrh., dS (I'M)), EnyUnzinnish. 5, pp. :-^07-jy.J).— This is a 

 description of the precipitin reaction as applied to the detection of vegetal)le 

 proteids, particularly in flour adulterations, and of the method of producing 

 the specific serum. 



The bleaching of flour, J. Buchwald and M. P. Neumann (Lamlio. Jahrh., 

 38 {I'.lOU). IJiij/iiiizimy-^l). 5, pp. 197-206, fig. 1). — The authors show that with 

 Alsoi)'s nitrogen dioxid apparatus the white color of fine flours may be rendered 

 2 or 3 shades lighter, but that with coarsely ground dark flour no bleaching 

 can be done. They attribute this to the fact that the latter have a higher 

 percentage of fat and contain larger sized and more seed hulls. The hulls 

 contain a dark tannic acid which can not be destroyed by the bleaching process. 

 The bleaching process was not found to increase the bakinf^ value of the flour, 

 but on the other hand it did not diminish it. 



The bleaching of flour, H. Rousset {Rev. Gen. Chim., 12 {1909), No. 19, 

 pp. 3(JS-3t(J, fujs. 7; ahs. in Ztschr. Angew. Chem., 22 {1909), No. 50, p. 2.'f29).— 

 The author discusses the different bleaching agents and their detection in the 

 flour, and reports results on attempts to bleach by-products of the milling 

 industry, such as bran. It is shown that the various bleaching agents have no 

 decolorizing power on bran. Tests with liquid bleaching substances also gave 

 negative results. The author shows by tests that it is possible to wash out 90 

 per cent of the starch content of the bran and recommends the use of this 

 product for sizing linen. The residue can be used, when mixed with molasses, 

 for cattle feed. 



Judging honey by the biological method, J. Langer {Arch. Ilijg., 77 {1909), 

 No. 3, pp. 308-330). — The author made a further study of the application of 

 the precipitin reaction for detecting honey adulteration. The proteid of honey 

 w^as found to be identical with that of pollen. By precipitating with ammonium 

 sulphate 10 gm. of pollen were found to contain 5.6 per cent of nitrogen, or 

 about 15 times as much as is found in natural honey. 



The method recommended by the author is as follows: Ten gm. of the honey 

 in question is dissolved in 10 cc. of water, filtered, and 5 cc. of this mixture 

 placed in each of 2 dializing thimbles (Schleicher and Schull) and dialized for 

 24 hours into distilled water. The water should be changed 2 or 3 times during 

 this interval. The dializates are then combined and made up to 30 cc, washings 

 and all, and filtered. From this mixture, 1 cc. of 10 and 20 per cent solutions 

 by volume are made up and placed in 2 graduated centrifuge tubes. A third 

 tube is filled with the original solution. To each of the 3 tubes there is added 

 1 cc. of specific serum and 1 drop of toluol, and they are then placed in the 

 incubator for 24 hours. After this the tubes are centrifuged for 5 minutes 

 and the height of the precipitate noted. Certain pure honeys did not give the 

 reaction. 



Detection of fuchsin in wines and sirups, A. Carobbio {Bol. Chim. Farm., 

 46 {1901), pp. 535-537; ahs. in Ztschr. Untersuch. Nahr. u. Oenu.^smth, 18 

 {1909), No. 11, p. 712). — The author describes 2 methods: 



(a) To 1 cc. of the sample is added 1 to 2 cc. of paraldehyde and then 4 to 5 

 drops of a 50 per cent i)otassium iodid i-olution in distilled water. After shak- 



