COMPARISON OF AMERICAN WHEATS. 17 



With regard to color, the relation is not so plain. With hard red 

 spring wheat the color seems to vary somewhat with the percentage 

 of sound wheat, but with the other classes there is no great regularity 

 so far as the averages are concerned. 



A further analysis of Table III reveals the greater value of test 

 weight and percentage of sound wheat in judging quality when these 

 two factors are considered together. It will be noted that the wheat 

 of highest quality from the standpoint of yield and color is both high 

 in test weight and in percentage of sound wheat and that the wheat 

 of lowest quality is low both in test weight and in percentage of sound 

 wheat. On the other hand, these figures would seem to indicate that 

 a sample which is low in test weight still gives a fairly high yield of 

 good-colored flour provided it is sound. They would also seem to 

 indicate the converse of this, that a sample low in percentage of 

 sound kernels but high in test weight may be of fairly good quality 

 as far as yield of flour and color are concerned, which indicates that 

 the percentage of unsound wheat is not always an absolute measure 

 of the extent of damage. 



INSEPARABLE FOREIGN MATERIAL, FLOUR YIELD, AND COLOR 



OF BREAD. 



In most of the samples milled, even after cleaning and scouring, 

 there remained small percentages of weed seeds, dirt, chaff, and other 

 grains which were ground when the wheat was milled. With the 

 wheat of all classes except the spring wheat, this was such a small 

 amount in the average sample as to be almost negligible. With 

 spring wheat, foreign matter consisting of a variety of weed seeds 

 and other grains, particularly wild oats, was present in amounts 

 sometimes ranging higher than 1| per cent. The only noticeable 

 effect of this material on the milling quality as revealed by a study 

 of averages is a reduction of milling yield, as is evidenced in Table 

 IV. This is what would be expected, only small quantities of these 

 substances getting into the flour, as they go largely into the bran 

 and shorts. No effect on the color of flour or bread is apparent from 

 these figures. The effects of specific impurities, such as rye, corn 

 cockle, kinghead, and vetch, have been described by R. C. Miller 1 

 and investigations along this line are being continued. 



1 Miller, R. C. Milling and baking tests of wheat containing admixtures of rye, corn 

 cockle, kinghead, and vetch. U. S. Dept. Agr. Bui. 328, 24 p., 10 fig., 2 pi. 1915. 



