NOTES ON FLOUR-STRENGTH. 171 



NOTES ON FLOUR-STRENGTH. 

 By P. B. Guthrie, f.i.c, f.c.s., and G. W. Norris. 



[Bead before ihe Royal Society of N. 8. Wales, October 6, 1909.] 



The term "strength" as applied to flour refers to that 

 combination of qualities which makes a flour valuable for 

 baking purposes. The problem as to what exactly con- 

 stitutes flour-strength and whether it is possible to devise 

 some ready means of determining this property without 

 having recourse to the always rather unsatisfactory baking 

 test, is one that has engaged the attention of many workers 

 in different parts of the world for some time and still 

 remains unsolved. 



In order to place the problem on a satisfactory basis, the 

 British Home-grown Wheat Committee has arrived at the 

 following definition of flour-strength as " The capacity to 

 make a big well-piled loaf." 1 Prof. Wood 2 further points 

 out that this is a complex of at least two factors, size and 

 shape of loaf. The definition thus stated appears to 

 include all the qualities the presence of which render a 

 flour of good baking quality and to provide a clear state- 

 ment of the problem presented to us. 



It does not, as will be seen, include the power of pro- 

 ducing weight of loaf. This property depends upon the 

 power of the flour to absorb water, and although this does 

 not perhaps strictly fall under the definition of strength, 

 we have nevertheless satisfied ourselves that it is a measure 

 of this quality and that those flours which absorb the larger 



1 A. E. Humphries, "The Improvement of English Wheat," Liverpool, 

 1905, also Humphries and Biffen, Journal Agric. Science, Vol. n, part i., 

 page 1. 



2 T. B. Wood, " The Chemistry of Strength of Wheat Flour/' Journ. 

 Agric. Science, Vol n, part ii, page 139. 



