40 
BULLETIN 1187, U. S. DEPARTMENT OF AGRICULTURE. 
forth until the gluten has collected into rolls. The operation should 
be carried out on a white paper so that the formation of gluten rolls 
can be noted. Wheat flour or other flours containing gluten show 
by this treatment a copious amount of gluten which absorbs the 
eosin with avidity assuming a carmine color. Rye and corn flour 
yield only a trace of gluten; buckwheat flour no appreciable amount. 
The preparations are best examined with the naked eye, thus gaining 
an idea of the amount of gluten present. If the flour is coarse, or 
contains a considerable quantity of bran elements, which is the case 
Fig. 32. — A desk with apparatus for qualitative estimation of the quality of the gluten in wheat and flour. 
in buckwheat flour and low-grade wheat flour, the test should be 
made after bolting, as the bran particles and coarse lumps interfere 
with the formation of gluten rolls. Figure 32 shows the apparatus 
necessary to make the Bamihl test. 
Quantitative Test}' 6 — Weigh 25 grams of flour and put it into a coffee 
cup, add tap water equivalent to trie water absorption value of the sam- 
ple, and work into a dough with a spatula or pestle, taking care that 
none of the material adheres to the vessel. Allow the dough to stand in 
water at room temperature for one hour. Knead gently under a stream 
13 Official and Tentative Methods of Analysis of the Association of Official Agricultural Chemists, 
vised to November 1, 1919. P. 169. 
Re- 
I 
