1« 



lAÜI.K VIll. 



(•oMi'cjsmuN OK TiiK .SOI. II» NArri:u i'i:i{ 



10.) PAKTS OK HKXTKOSK. 



Exp. 



Tinic and Toni|ier<ituro 



Dextrin 



Altjuuionoidi 



1 

 •> 



18Iioiir»ftt 10 12T. . 

 } lir. al V," 



1 1,1-.. :it ir." 



21.2 

 U.T 



M.r, 



28.10 

 26.3U 



After 1^ ii'iiirs ;it a low teiiiin.'ratiiir tlii' mni'iuit ordcstrin is 21.2 |>;irls for 

 (.•very 100 [nrl.'* of (k-xlrnso, but after lH>tli J lir. ami 2 lionrs lit 4.'»^, it rciimin^ 

 |iiac(icn11y tlic saino ami iilioiit two-tliinis of llic amount in tlic former cofc. 

 'J'lie most interesting!; fivct to l)j observed is Hit* vmiiition in llie ninonnt of tlie • 

 albimieiKiils; after IS l-.mirs at 10 12"C. it is very liltli; dilTtrent from tli« 

 anionnt dissolveil out in 2 lionrs at a tem|)criilnru of 4.'rC'., but after only ^ lioiir 

 ftt 4r*'G. the quantity in solution is only abfiut onc-eiglith iik inucli a« in the two 

 oilier cx|ierimentB. This l)oars ont the oliscrvations ma<le at lower tem|K>mture*, 

 viz. tliat lliP amount of albimti-noid matter ili.^solveJ is mainly nffi-cte»! by tliu 

 ilnratiiin of thi' e.xiteiimcnt. It is not only <!e|»en(leMt ujK'n th:if, for we wt) tho 

 i'lllnencc of a higher temier.itnrc in ilissolving the i;lbiimi>noi(Is inort» mpiilly, 2 

 1 onrs at 4ö^C. being more than eqi ivalent to 18 hours at lü-12°C. Tiius wo 

 ate again led t') the conelusion that the givater |Kirt of the nitrogenous matter 

 ill koji is insoluble in water, but that it is in sreli a state tliat the firolonge«! 

 contact with water renders it soluble. 



Although the effect of heat upon the mi.\ti:re of koji and water is tins 

 marked, when tho ckr.r solution has 1 eeu FepiRiteil by filtnilion from the 

 r.ndissolveil grains it is not fo iTipi<lly changed cillu-r by e.N] «>suro to heat or by 

 longer standing at the ordinary tem]K"niti;i-e of the nir. It is im|>ortnnt for us to 

 evamine tlie change in composition of the solution on heating, as in the exjien- 

 menta upon starch-pjstc to bo presently desiriW'd it is the filteri'il solution of 

 koji which is UFcd. The following table (p. 19) give« the results of ii numlterof 

 experinieids made by Watanalie Yuziiiu. gnvduati-, on tlu; eni.-el of healing 

 lillere.l Solutions of koji for one hour at the ?|X'(i(;ed tcn)p<"n\tun's, the same solu- 

 tion In-ing examineil for eoiii]arison aft^r .■■taiidin'/ at the i rdiii:irv temj>rniture 

 for the f.ime timo 



P.elow 4r»''o'. iho change in the compocilinn of the litpiiil is fo .•■mall th.it it 

 m ly pnuttiiiliy l>c negknteil. but lietwee k 4.'>'C. ami GO°C'. the efTirt is mueli 

 more markeil. .\n increase in the anioent of tolid niatter nnil in the dexlniM; 

 ocjui-s, jvreoiiipaiiietl Iiv a divrease in tlie HH-cihc n>latory |>ower. Thei«! reHults 

 are i-.iused by an al>sorption of water by the dextrin which is «»nvertcil into 

 dextrose anil thus the amount of >olid mitd-i in a given volmne of the liquid is 

 incivascd which, together with the smaller specilic rotatory power of flip dcxtn»fr. 

 lowers the sjiccilic rotatory |)owcr of the solnliim. 



