814 EXPERIMENT STATION RECORD. 



In regard to determining- the acidity of cane juice, P. A. Yoder (Jour. 

 Indue, and Engin. Cheni., 3 {1911), No. 9, pp. 640-6Jf6, figs. 2; abs. in Ztschr. 

 Angew. Chem., 25 {1912), No. 21, pp. 1082, 1083).— Most of the literature in 

 regard to the determination of acids in wine fermentation products, fruit 

 juice, etc., does not take into account the aconitic acid which is usually present, 

 and which constitutes in Louisiana cane juice most of the acidity present. The 

 utility of the well-known existing methods for isolating and determining the 

 various acids present and the behavior of these acids and their salts toward 

 solvents were studied. It was found that aconitic acid, succinic acid, and 

 lactic acid can be easily removed quantitatively from the juice by extraction 

 with ether, but tartaric, malic, and citric acids can not be isolated satisfactorily 

 by this method. 



In testing the solubility and the precipitability of the calcium salts of these 

 acids the salt of aconitic acid was found to have the same property which cal- 

 cium citrate possesses, i, e., precipitation by heat from its aqueous solution. 

 The solubility of calcium malate in 50 per cent alcohol gives a basis for a 

 method for separating it from other acids except lactic acids. The barium 

 salts behave like the calcium salts in regard to solubility. The separation of 

 aconitic acid from succinic acid in the shape of the acid ammonium salt was 

 not satisfactory. Deniges' method was satisfactory for detecting citric acid 

 but has the objectionable feature that it is also positive for aconitic acid. 



A practical illustration for determining the several acids from cane juice is 

 given. 



Some recent work on molasses analysis, W. JE. Cross {La. Planter, ^8 

 {1912), No. 22, pp. 382, 383). — A critical review of the literature in this regard. 



The determination of nitrogen in betain, H. Stoltzenbeeger {Ztschr. Ver. 

 Deut. Zuckerindus., 1910, No. 615. II, pp. 440-Jf45). — ^This is a contribution 

 to the question of determining nitrogen in molasses and vinasse. 



Complete oxidation of the betain can only be brought about by heating the 

 sample with concentrated sulphuric acid for several hours. By the addition of 

 copper sulphate, mercuric oxid, and phosphorus pentoxid to the acid mixture, 

 the oxidation process can be accelerated considerably. To determine the 

 nitrogen in substances containing betain the following procedure is recom- 

 mended by the author: 



About .3 gm. of molasses or 2 gm. of vinasse is placed in a 500 cc. Kjeldahl 

 flask and 25 cc. of a sulphuric acid-phosphorus pentoxid mixture (100 gm. of 

 phosphorus pentoxid in a liter of acid) and 1 gm. of powdered potassium 

 sulphate and 1 gm. of mercuric oxid added. The mixture is then heated until 

 decolorized, and 1 hour in addition. After cooling and diluting with 120 cc. 

 of water, 2.2 gm. of powdered .sodium thiosulphate and J teaspoonful of pipe- 

 clay are added ; the pieces of clay must have the size of a pinhead or of small 

 shot. After setting up a receiver which contains 50 cc. of decinormal hydro- 

 chloric or sulphuric acid for collecting the distillate, 90 cc. of a 22 per cent 

 sodium hydrate solution is added to the mixture, the flask quickly connected 

 with the condenser and distilled until bumping begins. The remainder of the 

 process is the usual one. 



Extraction of oil from the olive, E. Mingioli (Petite Rev. Agr. et Hort., 

 18 (1912), No. 421, pp. 133, 131,). — ^A description of the Acapulco method and 

 its advantages and disadvantages. 



A comparative study of methods for the determination of hard and 

 total soft resins in the hop, H. V. Tartar and C. E. Bradley (Jour. Indus, 

 and Engin. Chem., J, (1912), No. 3, pp. 209-212). — This is a comparative study 

 of some of the present methods, including Briant and Meacham's, Siller's, 



