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absorbs the dye, and on a white background becomes very conspicuous because of its 

 beautiful pink color. A description of the procedure follows: 



Place side by side on a microscopic slide 1.5 mg of the flour and a drop of water 

 containing 0.2 gram of eosin in 1,000 cc. Allow the slide to rest on a sheet of white 

 paper and carefully mix the flour with the liquid by means of a cover glass, held 

 between the thumb and finger in such a manner that it is raised slightly above the 

 slide taking care that none of the flour escapes from beneath it. Finally, allow the 



2 3 



FIG. 6. Bamihl gluten test (X4): 1, Pure rye flour showing only trace of gluten; 2, a mixture of 60 

 per cent rye and 40 per cent wheat; 3, pure wheat flour showing gluten masses. 



cover glass to rest on the slide and rub it back and forth until the gluten, if present, 

 forms into rolls or masses. Conduct parallel tests for comparison on pure wheat and 

 pure rye flour. Proceeding in this manner, wheat flour yields an abundance of gluten, 

 which is stained a beautiful pink color by the eosin, whereas rye flour yields none, or 

 else only traces which are scarcely visible to the naked eye. Mixtures of rye and 

 wheat flour yield variable quantities of gluten, depending upon the proportion of the 

 two flours and their source. 



In testing graham flour, buckwheat flour, and other cereal products containing 

 considerable quantities of bran tissues or coarse lumps of any kind, the flour should 

 be sifted through a bolting cloth before applying the test. The bolting is conveniently 



