The Students' Guide in Quantitative Analysis - Free Ebooks Library

DETERMINATION OF SUGAR, 119
A convenient apparatus for the extraction of sugar is
described by Prof. S. W. Johnson, in Am. J. of Sci. (3)xiii.
page 196(1877).
D. — Determination of total Non-volatile Matter.
Evaporate 10 to 20 g;rms. milk to dryness, with the
addition of a little acetic acid, and ignite the residue in a
muffle furnace, at the lowest possible temperature.
E- — Dotermination of Protein Compounds.
Subtract the sum of tlie butter, sugar, and ash from the
total dry substance, and the remainder is chiefly casein.
For other methods, see " A Method for the Analysis of
Milk," by E. H. von Baumhauer, Am. Chem,^ Vol. VII., 191.
Analysis No. 35. — Raw Sugar.
A. — Determination of Moistiure.
Heat a weighed amount of sugar at 110° until it no
longer loses in wciglit. Loss ^moisture.
E.— Dotermination of Ash.
Weigh off ten grms. in a platinum dish. Either burn the
sugar direct, or add a few drops of cone. H2S04and heat
very cautiously in a gas muffle. Weigh the ash.
The two methods do not give results at all concordant
the latter is the French method, and the results are called
" the salts," after subtracting one-ninth, but this is seldom
correct, though the ash burns very white.
C— Determination of Grape Sugar,
(i) Qualitative reactions. Glucose is colored dark-
;