22 



EXPERIMENT STATION RECORD, 



The identification and quantitative determination of sodium chlorid in 

 feeds, A. Steigel (Landw. Vers. Stat., 82 (1913), No. 1-2, pp. 149-158).— Salt 

 is said to be added to linseed for the purpose of aiding the extraction of the 

 oil. When added to the meal after extraction it is evidently done for the pur- 

 pose of increasing its palatability, and probably at times to cover up a moldy 

 feed or a feed adulterated witli materials of low nutritive value. 



An exact determination of sodium chlorid in feeding stuffs and also in 

 condimental foods can be made by extracting the substance by shaking it with 

 water. The iiqueous solution obtained is evaporated with the addition of 

 sodium carbonate and potassium nitrate and is then ashed. The chlorin is 

 determined in a solution of the residue. Direct ashing of the feed is not per- 

 missible because losses of chlorin occur. The water extracts can not be titrated 

 directly with silver nitrate using potassium chromate as an indicator on account 

 of lack of sharpness in the end-point, and titration according to Volhard's 

 method in a nitric acid solution is recommended. As a preliminary test the 

 sodium chlorid can be separated from the feed with chloroform. 



The action of refined sugar on Fehling's solution in the Herzfeld method 

 for the determination of invert sugar, F. Stbohmer {Osterr. JJngar. Ztschr. 

 Zuckerindus. u. Landw., 42 (1913), Ao. 3, pp. 539-645; abs. in Chem. Abs., 7 

 {1913), No. 23, p. 4091). — When Fehling's solution is heated according to the 

 directions prescribed for this method there is a tendency toward the separation 

 of varying amounts of cuprous oxid. The separation increases even though the 

 sugar is free from invert sugar because of the fact that even chemically pure 

 saccharose has a slight reducing power. In an alkaline solution pure saccharose 

 undergoes inversion, the degree being proportional to the alkalinity, the length 

 of time of boiling, and the quantity of saccharose entering into reaction. No 

 definite proportional relation seems to exist between the amount of organic and 

 inorganic nonsugars on the one hand and the reducing ix)wer on the other. 

 When a reduction below 50 mg. of metallic copper is obtained, this error may be 

 disregarded. 



Bacteriological investigations of sugar cane products, W. L. Owen (Louisi- 

 ana Stas. Bill. 146 (1914), pp. 78, figs. 6).— In anticipation of future demands 

 for reliable methods for use in the sugarhouse, this investigation of the com- 

 pai-ative values of various culture media for the quantitative estimation of the 

 micro-organisms in 'sugar-house products was instituted. 



The relative rank of the different culture media employed is given in the 

 following table : 



Comparative value of culture media for estimation of micro-organisms in sugar- 

 house products. 



Raw juice. 



Clarified juice. 



Massecuite. 



Raw sugar. 



Plain agar — 

 Sucrose agar. . 



Raw juice 



Peptone agar. 



Raw sugar 



Peptone agar. 



Molasses 



Peptone agar . 

 Molasses agar. 



Raw juice agar . 

 Raw sugar agar. 



Sucrose agar.. 



Plain agar 



Raw juice.... 

 Peptone agar. 



Molasses 



Peptone agar. 



Raw juice agar. 



Raw juice 



Peptone agar. . . 

 Molasses agar. . . 



Raw sugar agar. 



Raw juice agar. 



Plain agar 



Raw juice 



Peptone agar... 



Molasses 



Peptone agar. . . 



Molasses agar. 

 Sucrose agar. . 



Raw juice 



Peptone agar 



Raw sugar agar. 



Sucrose agar 50 per ct. 

 Sucrose agar 25 per ct. 



Plain agar. 



Sucrose agar 10 per ct. 



