802 EXPERIMEXT 3TATI0X EECOED. 



Chemical changes in the souring of milk, L. L. Tan Slyke and A. W. Bos- 

 worth (New York State Sta. Tech. Bui. 48 (1916), pp. 12; Jour. Biol. Chem., 

 24 (1916), No. 3, pp. 191-202). — The results of the investigation reported demon- 

 strate that about 22 per cent of the Uictose of milk is changed by the lactic 

 acid bacteria during the process of souring. Of this amount about 88.5 per 

 cent is converted into lactic acid. The citric acid present in the milk com- 

 pletely disappears, being decomposed into acetic acid and carbon dioxid by 

 Bacterium lactis aerogencs. The insoluble inorganic constituents of normal 

 milk are made soluble by the acid resulting from bacterial action. The albumin 

 which in normal milk only partly passes through a porous porcelain filter is 

 so changed in some manner during the souring as to pass completely through 

 such a filter. The calcium caseinate of normal milk is completely converted 

 into free protein and precipitated as such, the calcium forming calcium lactate 

 which is soluble in the serum. 



The rate and extent of chemical change under given conditions was also 

 studied. The greatest change of conversion of milk sugar into lactic acid was 

 found to occur between the tenth and the twenty-fourth hour after inoculation. 

 The acidity increased rapidly during the first 24 hours, the rate of increase 

 diminishing after this time. The amount of albumin nitrogen in milk serum 

 was found to increase with the increase of acidity. All of the albumin of the 

 milk appeared in the serum in 14 hours. 



The experimental methods used in the investigation were those described in 

 the bulletin previously noted (E. S. R., 32. p. G07>. 



Chemical changes occun-ing during the ripening of the wild goose plum, 

 J. S. IMcH.VRGUE (Jour. Aiiicr. Chem. Sue, 38 (1016), No. 3, pp. 718-722).— Vvum 

 the results of a study at the Kentucky Experiment Station the author concludes 

 that there is a gradual diminution in the acidity of the fruit during the rli>en- 

 ing period, and at the same time an increase in the amount of reducing sugars 

 formed. The greatest increase in total sugars occurs in passing from the un- 

 ripe to the ripe condition. Saccharose plays a very important part in the 

 ripening of this fruit, which suggests the idea that a fruit is just ripe when it 

 contains the maximum anmunt of saccharo.se. This plum contains the euzym 

 invertase, which is apparently most active in the passage of the fruit from the 

 ripe to the overripe stage. 



The essential oil of sugi (Cryptomeria japonica) leaves, S. Uchida (Jour. 

 Amer. Chem. Soc., 38 (1916), No. 3, pp. 687-699).— The .sugi is a coniferous tree 

 indigenous to Japan, and extensively cultivated as a valuable timber. The 

 essential oil of the leaves, obtained by steam distillation, was found to contain 

 the following substances: d— a— pinene; dipentene; an alcohol (CioHisO, h. p.= 

 212-214°, (iis=0.9414, 71d"'=1.4832) ; cadinene; a sesquiterpene with two 

 double linkings (C,.H„, b. p.=266-268°. rfi5=z0.9335. np" '=1.5041, [a]D = + 

 15.19° in a 6.08 per cent chloroform solution) ; a .sesquiterpene alcohol 

 (CisHzeO, b. p.=2S4-2S6°, r7,5..=O.OG23, 71d="=1.5048, [0]^"= +16.70° in a 5 

 per cent chloroform solution) ; a new diterpene (Ca^Hs:, b. p.7ao=345°, b. p.i6= 

 198, [a]D=z— 34.22° in a 4.67 per cent chloroform solution) for which the 

 author proposes the name " a-cryptomerene " ; a lactone (CmHsjO;) ; caprylic 

 acid in combination with the alcohol ; higher fatty acids in a free state ; and a 

 blue oil '* azulene." 



The relative proportion of the above constituents present was also deter- 

 mined. 



Essential oil of Formosan hinoki (Chamaecyparis obtusa) wood, S. IVinDA 

 (Jour. Amer. Chrm. Soc., 38 (1916), No. 3, pp. 699-702) .—The hinoki tree is ex- 

 tensively grown in .Tapan and furnishes a timber wood of superior quality. 

 The crude (»il ul)taln(Ml by dry tlistillath.n of the wood was rectifieil bv steam 



