24 BULLETIN 328, U. S. DEPARTMENT OF AGRICULTURE. 



Special experiments were made to ascertain what effects the 

 presence of rye, kinghead, corn cockle, or wild-vetch seed in wheat 

 has on milling and baking qualities. 



A sufficient amount of wheat of one variety was purchased to make 

 all the milling tests for each year, in order to have a basis for com- 

 parison of all tests with the impurities. Different percentages of each 

 impurity were mixed with wheat samples, which were then milled 

 and baking tests made with the flour. 



The results of these tests show that the presence of more than 2 

 per cent of any of these impurities in wheat as milled has detrimental 

 effects on the milling and baking qualities. 



The deleterious effects of rye in wheat are less pronounced than 

 those of corn cockle, kinghead, or vetch seed. If present in wheat 

 in amounts as high as 2 per cent or more, rye lowers the quality of the 

 bread. 



Corn cockle seems to have exceedingly injurious effects on the 

 volume, color, and texture of the loaf, and when present in amounts 

 of 3 per cent or more reduces the percentage of water absorption of 

 the flour. 



Kinghead in wheat in appreciable amounts materially lowers the 

 flour yield, and the detrimental effects of this impurity in the flour 

 are especially noticeable in the dirty color of the crumb and the 

 coarse, uneven texture of the bread baked from such flour. 



Vetch seed in wheat will reduce the size of the loaf and give to the 

 bread a yellowish tinge and a disagreeable odor and flavor charac- 

 teristic of vetch. 



Corn-cockle seed is a more objectionable impurity in wheat than 

 rye, kinghead, or wild vetch, since it contains a poisonous element 

 known as saponin, or sapotoxin, the presence of which is very unde- 

 sirable in flour or bread. 



ADDITIONAL COPIES 



OF THIS PUBLICATION MAY BE PROCURED FROM 



THE SUPERINTENDENT OF DOCUMENTS 



GOVERNMENT PRINTING OFFICE 



WASHINGTON, D. C. 



AT 



10 CENTS PER COPY 



