260 EXPERIMENT STATION RECOED. 



investigations on the subject witla s]iec-ial reference to determining tlie ]iurity 

 of rnsplierry .inice and rasphorry sirnp. 



Marmalade niaking by English methods, C. Rapp (Die Manueladenfuhri- 

 katioji iKtcli riiglixclicin Vcrfahren. "Magdeburg and. Viniiia: HchaJIcJin tG 

 Wollbiiick, 1907, pp. 12.',, figs. J,.l,; rev. in Osterr. Chevi. Ztg., 10 {1907), No. 8, p. 

 107). — The autlior discusses materials used in marmalade malving, different 

 sorts of machinery, liandlhig and shipping goods, and related questions. 



Concerning Liebig's meat extract, II, KutschePv {ZrnthJ. PJiy<siol., 21 

 (1907), No. 2, pp. 33-35). — Oblitin, histidin, and a new meat base for which 

 the tentative name " vitiatin " is proposed, were identified as constituents of 

 meat extract. Vitiatin is apparently related to guanidin, methylguanidin, di- 

 methylguanidin, creatin, and creatinin, and the author liopes that it will prove 

 to be the mother substance of these bodies. Earlier work has been noted 

 (E. S. R., 17. p. 790). 



Preservation of meat (Osterr. Mil. Ztsclir., 2 (1906), p. 1817; ahs. in Hyg. 

 Zenthl., 2 (1907), No. 14, pp. '/-jI, J,.}2). — In the system of preserving meat 

 described, the meat is dried in. a vacuum at a temperature less than 0° C. It 

 is stated that the flesh thus dried remains porous, keeps well, and, after soak- 

 ing in water, closely resembles fresh meat in appearance and flavor. 



A contribution to the chemistry of the bleaching of flour, S. Avery (Jour. 

 Amer. CJtciit. l^oc, 29 (1907), No. //, pp. 571-37'/). — From experiments which 

 were carried on at the Nebraska Experiment Station with different bleaching 

 agents, the author, concludes that " the maximum bleaching effect, without 

 regard to the quantity of the reagent, can be obtained by the use of bromiu. 

 The other reagents follow in the order named : Chlorin, sulphur dioxid, nitrogen 

 peroxid. A given weight of nitrogen peroxid will bleach a far greater quantity 

 of flour than the same weight of any of the other reagents mentioned. All 

 samples of flour bleached with nitrogen peroxid, in so far as tested, respond to 

 the Griess test for nitriies. Samples stored in laboratories and in mills where 

 bleachers are used, connnonly respond to the same test. A sample exposed, 

 however, for 13 months in an office not containing any electric or gas lights 

 failed to respond to the Griess test. 



"A sample of the flour under consideration was placed in a layer Jj in. thick 

 between plates of glass. The plates were bound together at the edges with 

 adhesive tape. The whole was exposed to the action of sunlight by placing in 

 direct sunlight and reflecting also the rays against the reverse side by a mirror. 

 The sample was bleached by an exposure of 2 hours. 



" Nitrogen peroxid mixed with an excess of ozone shows the same bleaching 

 effect as when mixed with air. The bleaching is due solely to the peroxid 

 present." 



The specific yellow coloring matter of wheat occurs dissolved in tlie wheat 

 oil and may be extracted with benzene or other solvents, the extracted flour, 

 as the author points out, being almost white. It was found that exposure to 

 direct sunlight removed the color of a benzene solution of wheat fat in .3 hours. 

 When a sample was shaken with a very dilute solution of nitrous acid bleaching 

 was instantaneous. With dilute bromin water the effect was less rapid. Slow 

 bleaching was effected with a solution of sulphurous acid in large excess. 



" Hydrogen peroxid solution, on shaking with the benzene solution of the oil 

 and coloring matter, gave no bleaching effect. This was true in acid, neutral, 

 and basic solutions. 



"A solution of the colored oil in aceton(> was treated with a trace of water and 

 alumiimm amalgam. The color was not clianged. Zinc dust and acetic acid 

 were also without effect." 



