2S4 



SCIENTIFIC AGRICULTURE. 



May, 1922 



Siheri&n. Red 7ife. W'hite Fife. Marquis. Kitchener 



Kuhy. 





Hed Bobs. Taylors V/onder. Kutar.ka. 



Pelissier. Standard, 



Loaves from the Standard Varieties of the 1918 Crop. 



(Note the sunken top of the Ruby loaf and that the loaves from the durum wheats 



are lacking in volume.) 



The greater part of Saskatchewan 

 wheat, liowever, is used for the man- 

 ufacture of bread flour. Therefore, in 

 this ease, quality in wh«at is indicated by 

 its suitability for the manufacture of 

 bread flour and by the characteristics of 

 this flour which determine its suitability 

 for tlie making of bread. In otiier words, 

 we must consider both the milling quality 

 of the wheat and the baking quality of the 

 flour. 



Milling Quality 



The milling quality of a wheat as de- 

 termined by the milling test depends 

 chiefly upon two factors : first, the yield 

 of flour, and second, the color of the flour. 

 These two factors are more or less cor- 

 related. By removing all possible flour 

 from the bran the miller is able to obtain 

 the greatest yield, but this is usually de- 

 trimental to the color. Again, by milling 

 the wheat so as to obtain flour of the best 

 possible color, the yield is proportionately 

 lowered. The miller must tlierefore bal- 

 ance these two factors, the quantitative 

 factor of flour yield and the qualitative 

 factor of flour color, so as to give him the 

 greatest net returns. The particular 

 wlu> i*^ wliich may be milled so as to keep 

 both of these factors high is considered to 



be (). high milling nualitv. 



The yield of flour as determined by the 

 milling test is expressed in percent of the 

 wheat milled and the color of the flour 

 described or scored. The importance of 

 flour color is due to the consumer's con- 

 sistent demand for white bread. In gen- 

 eral the best flour should be almost white 

 with a faint creamy tinge. 

 Baking- Quality 



The baking quality of a flour is indi- 

 cated chiefly by the elasticity of the glu- 

 ten, the volume of the loaf, the texture 

 of the loaf, and by the water absorption. 



The elasticity of the gluten and loaf 

 volume may best be considered together 

 as it is upon the elastic properties of the 

 moist gluten in the dough that the volume 

 of the loaf is dependent. As the yeast 

 organism acts upon the starch of the flour 

 carbon-dioxide and alcohol are given off. 

 The mass of dough then becomes filled 

 with innumerable tiny cavities which ex- 

 pand further and further as the volume 

 of the gas increases. Finally,- if the loaf 

 is not heated to a baking temperature, 

 the elastic walls of the cavities become 

 distended to the limit and burst, and the 

 mass of dough begins falling back to its 

 former volume. In the process of bread 

 making the dough is placed in the oven 

 before it reaches this stage. The walls 

 of the cavities then become stiffened 



