414 EXPERIMENT STATION EECORD. 



" Tlie temperature to which the fat had previously been subjected seemed to 

 make no difference in the hardness provided the samples were treated as 

 described. The determinations can be made with great rapidity after the 

 samples are proi)erly prepared. More closely agreeing duplicate determina- 

 tions are procurable with this method in examining manufactured butter than 

 in examining the rendered fat. The results obtained, however, are likely to be 

 very greatly affected by variations in the method of preparing the butter; 

 they probably will not truly reiiresont the pro])('rties of the fat itself. ■ 



" The apparatus with slight modifications should be useful for other work of 

 a similar nature." 



Estimation of sucrose in the presence of lactose and in th,e milk prepara- 

 tions, J. N. Rakshit {Jour. Indus, and Engin. Chem., 6 {WUi), No. Jf, pp. 

 307 SOS). — In the analyses of several cans of condensed milk it was observed 

 that boiling for 40 minutes with citric acid solution was not sufficient for 

 inversion, and a method is suggested which is simple and which suffices for all 

 ])ractlcal purposes. It consists of determining the ]jercentage of lactose by 

 titi-ation with Fehling's solution. "Then a measured quantity of Fehling's 

 solution is boiled with a calculated quantity of sugar solution so that all the 

 copper may be thrown out of solution with the simultaneous consequent decom- 

 position of all lactose, when cane sugar alone will be left in solution. This can 

 be readily estimated after the usual inversion and neutralization." 



Boric acid as a milk preservative and its detection, H. Kuhl {Ztschr. 

 FJehch u. MUvhliyg., 2.'t {1014), No. J//, pp. 329-333).— For detecting very small 

 amounts of boric acid it is necessary to examine the milk ash. Small amounts, 

 however, may be detected by acidifying 50 cc. of the milk with 1 cc. of hydro- 

 chloric acid if boric acid is suspected and 2 cc. of hydrochloric acid if borax is 

 thought to be present. The filtered opalescent serum is then tested with 

 curcuma paper and the paper dried immediately on a watch glass over a water 

 bath. A red coloration indicates boric acid or borax, and if a drop of ammonia 

 is added to the paper it becomes bluish black. 



As the germicidal action of boric acid is low and the substance is deleterious 

 to human health, the author believes that its use as a preservative should be 

 barred. 



Comparative investigations on the utilization of the Mai and Rheinberger 

 method for determining the total solids in cheese, H. Weigmann and E. 

 Haglund (Ztschr. Untersuch. Nahr. u. Qcnussmil., 27 (1914), -ZVo. 1-3, pp. 77- 

 83). — ^The Mai and Rheinberger method gave from 1.84 to 3.7 per cent less mois- 

 ture than did the German official sea sand method. Deferring the time of 

 reading the liquid column in the first-uamed method did not alter the results. 

 In order to determine whether the method has some errors, as in the decompo- 

 sition of the cheese mass, tests were made with fresh acid and rennet curd, 

 etc. The distillate from curd contained besides water decomposition products 

 (ammoniacal), all distillates being strongly alkaline. The method must conse- 

 quently give figures which are too high, and the sea sand method is preferred. 



A rapid method for determining fat in cheese, Tkichekt (AUgiiucr Monats- 

 schr. Milch w. u. Vieh!:., 2 (191^), No. 1, pp. 13, 14). — In large cheese-selling 

 establishments it is often necessary to have a rapid method for determining 

 the fat content of cheese. For this work the butyrometer previously suggested 

 by the author for determining fat in dried milk and graduated from to 35 

 may be used. 



In this method, 2.5 gm. of the cheese is dissolved in a porcelain dish with 

 8 cc. of sulphuric acid, specific gravity l.G, and after solution the mixture is 

 ])oured into the butyrometer. The dish is then rinsed with 8 cc. more of sul- 

 phuric acid, the washings poured into the butyrometer. 5 cc. of amyl alcohol 



