102 ENVIRONMENT AND MILLING QUALITIES. 



in the same locality in different seasons. This character, although 

 affecting the yield, cannot be regarded as a criterion of quality.' 



3. Composition. — Much of the work on the subject of the 

 effect of environment on the characters of the wheat grain has 

 been concerned with the effect of change of environment on the 

 nitrogen content of the grain — the nitrogen content being taken as 

 the most convenient indication of the strength of a wheat. Un- 

 fortunately although, as a rule, the higher the nitrogen content the 

 stronger the flour, nevertheless there are exceptions, some wheats 

 high in nitrogen giving very weak flours.^ The total nitrogen 

 content is, therefore, not nearly so reliable a test of strength as that 

 obtained by milling and baking the sample. Moreover the quality 

 of a wheat does not depend entirely on the strength of the flour 

 but on many other characters which go to form what is known as 

 quality. Although a great deal of work has been done on the 

 chemical composition of wheat and of wheat flour, yet no accurate 

 relation has hitherto been found between the chemical composition 

 and the bread-making value of wheat. Wood's^ researches at 

 Cambridge seem to indicate that the physical properties of the 

 gluten are of greater importance than chemical composition. 



4. Consistency. — The effect of environment on the consistency 

 of the wheat grain, i.e., its translucent or starchy appearance has 

 been perhaps more thoroughly investigated than any other aspect 

 of the question. There is no doubt that consistency depends very 

 largely on the soil, on the available moisture and on the nutrition 

 of the crop.^ From the milling point of view the consistency of 

 the wheat grain is of the highest importance and to some extent 

 determines the value of the crop. Differences in consistency 

 affect the market value of wheat in two ways. Firstly, millers 

 like wheats of uniform consistency as in the conditioning or 

 adjustment of water previous to grinding, it is an advantage to 

 handle hard and soft wheats separately and a mixture of hard and 

 soft wheats often leads to trouble and loss. Secondly, as a rule, 



' Cserhati, Ztschr. landw. Versuchsw. in ester reich, 9 (1906), No. 10. 

 Hall, Journal of the Borird of Agriculture {England), Vol. XI, No. fi. 

 3 Wood, Journal of Agricnllurnl Science, Vol. IT, 1907, p. 160. 

 * Howard and Howard, 1. c. 



