KXPERIMENTAL MILLING AND BAKING. 
39 
The method is essentially the same as that described by Alway 
and Bishop. 11 Briefly, about 2 grams of air-dry whole kernels, the 
exact weight of which is known, are placed in a Kjeldahl flask with 
25 cubic centimeters of sulphuric acid, 10 grams of sodium sulphate, 
0.7 gram mercuric oxid, and digested and distilled as above. If the 
data arc desired on a water-free basis, a longer time is necessary 
than that consumed in making tests on a ground sample, as it takes 
approximately 72 hours to drive all the water out of the whole kernels. 
Fig. 31. — Laboratory table showing some of the chemicals used in making protein tests. Apparatus in 
background used for making color tests on barley and oats. Sieve for washing gluten out of flour to the 
right. 
Nitrogen determinations can, of course, be made on the water-free 
sample. 
CRUDE GLUTEN IN FLOUR. 
Qualitative Test 12 — (Bamihl) — Place a very small quantity (about 
1.5 milligrams) of the flour on a microscope slide, add a drop 
of water containing 0.2 gram of water-soluble eosin in 1 liter. 
and mix by means of a cover glass, holding the latter at first 
in such a manner that it is raised slightly above the slide, and 
taking care that none of the flour escapes from beneath it. Finally, 
allow the cover glass to rest on the slide and rub it back and 
11 Nebraska Agricultural Experiment Station, 23d Annual Report, 1908-09, p. 21-25; The Determination 
of Nitrogen in Dried Unground Cereals, by F. J. Alway and E. S. Bishop. 
" Official and Tentative Methods of Analysis of the Association of Official Agricultural Chemists. Re- 
vised to November 1, 1919. P. 169. 
