112 Kansas Academy of Sciefice. 



charine material. Coffee grounds, if made into a powder as fine as flour, is 

 worth experimenting with, since they contain as unexpectedly large per- 

 centage of fat and a like proportion of protein, and during the process of 

 baking no caffein could remain should there be any unextracted alkaloids 

 in them. Some crackers made by us and flavored with cinnamon or ginger 

 have proven quite palatable. As to their value as a dietary, it will take 

 some time to determine and give any satisfactory report. 



Prices of corn starch flour January 10, 1917: 100 pounds (Chicago), $3.05; 100 

 pounds (Lawrence), $3.29. 



From Bakers Weekly, December 2, 1916. File. Addenda to article for Kansas 

 Academy of Science, January 12, 1917. 



Determining- the Strength of Flour. 



Prof. T. B. Wood, Cambridge University. 



After seven years of investigation the author has worked out the 

 following theory on the strength of wheat flours, which has finally 

 enabled him to devise a method which promises to be both accurate and 

 rigid, and to require a very small amount of flour. The strength of a 

 wheat may be defined as the power of making a large loaf of good shape 

 and texture. Evidently strength is a complex of at least two factors, 

 size and shape, which are likely to be quite independent of each other. 

 Not infrequently, for instance, wheats are met with which make large 

 loaves of bad shape or small loaves of good shape. 



A FEASIBLE IDEA. 



It seemed a feasible idea that the size of the loaf might depend on 

 the volume of gas formed when the yeast was mixed with different 

 flours. On mixing different flours with water and yeast it was found 

 that for the first two or three hours they all gave off gas at about the 

 same rate. The reason of this is that all flours contain about the same 

 amount of sugar, approximately 1 per cent, so that at the beginning of 

 the bread fermentation all flours provide the yeast with about the same 

 amount of sugar for food. But this small amount of sugar is soon ex- 

 hausted, and for its subsequent growth the yeast is dependent on the 

 transformation of some of the starch of the flour into sugar. Wheat, 

 like many other seeds, contains a ferment or enzyme called diatase, 

 which has the power of changing starch into sugar, and the activity of 

 this ferment varies greatly in different wheats. The more active the 

 ferment in a flour, the more rapid the formation of sugar. Conse- 

 quently the more rapid the yeast will grow, and the greater will be the 

 volume of gas produced in the later stages of fermentation in the dough. 



ESTIMATING THE SIZE. 



From these facts it is quite easy to devise a method of estimating 

 how large a loaf any given flour will produce. Twenty grams of flour 

 are weighed out and put into a wide-mouthed bottle. A flask of water 

 is warmed at 40° C. Of this, 100 cc. is measured out and into 2^ 

 grams of compressed yeast is intimately mixed, 20 cc. of the mixture 

 being added to the 20 grams of flour in the bottle. The flour and yeast 

 water are then mixed into a cream by stirring with a glass rod. The 



i 



