16 EXPEEIMEISTT STATION EECORD. 



The detection of cotton-seed hulls in cotton-seed meal, C. Gkimme {Ghem. 

 Ztg., 38 (1914), No. IS, pp. 137-139, fig. J).— It is stated that the difficulties 

 encountered in the Fraps method (E. S. R., 20, p. 90S) may be obviated if 

 2 gm. of the meal after being freed from fat is digested for 30 minutes from 

 the time of boiling with 200 cc. of a 1 per cent hydrochloric acid solution, 

 diluted to 1,000 ce. with hot water and filtered through asbestos. The residue 

 on the filter is washed acid-free with hot water, three times with alcohol, 

 and once with ether, dried at from 105 to 110° C. to constant weight, ignited, 

 and the amount of ash deducted from the first weighing. The percentage of 



hulls is calculated by the formula a:= ^^~ J ■ in which y represents the 



oy 



amount of ash-free residue. The results agree well with those given by the 

 Fraps method. 



Note on the precipitation of lactalbumin in cow's milk, W. O. Walker 

 and A. F. G. Cadenhead {Jour. Indus, and Engin. Chem., 6 {1914), ^o. 7, pp. 

 573, 574). — The official method for estimating lactalbumin in milli, i. e., pre- 

 cipitation with a 0.3 per cent acetic acid solution from a neutral solution from 

 which casein has been removed, was found unsatisfactory. 



Sebelien's method "■ gave more satisfactory and uniform results and was 

 quite as convenient, both from the standpoint of time and manipulation. The 

 reagent, which was Almen's, was composed of 4 gm. of nitrogen-free tannic 

 acid, 190 cc. of 50 per cent alcohol, and 8 cc. of 25 per cent acetic acid. The 

 best results were obtained with from 10 to 12 cc. of the reagent for a 10 gm. 

 sample of milli. " The clear filtrate, with washings from the casein — which 

 was precipitated according to the official method — was neutralized with sodium 

 hydroxid with the addition of a few drops of phenolphthalein. The pink color 

 was then discharged with one drop of 10 per cent acetic acid, the filtrate, 

 about 200 to 250 cc. in volume, was heated to 40-45° C, and the reagent added, 

 the mixture stirred continually for two minutes and then allowed to stand 

 for half an hour before filtering, when the albumin was precipitated in a very 

 fine flocculent form. When filtered immediately after precipitation, some of 

 the precipitate invariably passed through the paper. The precipitate and the 

 paper was then treated according to the official Kjeldahl-Gunning method, the 

 nitrogen determined, and the result multiplied by 6.34 for the albumin. The 

 protein in the filtrate from the above operation was determined in each case 

 and was found to show an average of 0.1 per cent." 



Comparison of methods for the estimation of fat in cream with special 

 reference to Sichler's " alcohol sin-acid" method, E. Blanck {Milchw. ZentU., 

 43 {1914), No. 12, pp. 316-325). — The Sichler alcohol sin-acid method '(E. S. R., 

 16, p. 506) gave good results, which agreed with those yielded by the Gerber 

 and Vieth methods. The results by the Rose-Gottlieb method with the same 

 milks were slightly lower. 



The alkali method for the determination of fat in ice cream and condensed 

 milk, C. M. Bradbury {Va. Dairy and Food Div. Giro. 42 {1914), pp. 4)- — ^An 

 adaptation of the Short method " for determining fat in milk and cream to the 

 determination of fat in ice cream and condensed milk. 



A rapid method for the determination of sodium chlorid in butter and its 

 substitutes, T. M. Rector {Abs. in Science, n. ser., 39 {1914), No. 1017, p. 952). — 

 Sodium chlorid is determined by titration with silver nitrate with a chromate 

 indicator, in a water solution of a weighed sample of butter in the presence of 



« Hoppe-Seyler's Ztschr. Physiol. Chem., 13 (1889) No. 1-2, pp. 135-180. 

 J-Wisconsiu Sta. Bui. 16 (1888), pp. 14, pi, 1. 



