The conditions for the production of sugars in the malting of barley have been carefully studied and are comparatively well known. That sugars are produced, in comparatively large amounts, when flour and water are mixed and allowed to digest a t warm temperatures, is not so well known. Jago,' in determining the diastatic capacity of malt extract, found that flour alone when mixed with water and allowed to digest for four hours a t 60' showed large diastatic activity. (I) It contains large

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... ties of soluble carbohydrates, mostly in the form of maltose and glucose. (2) It also contains enzymes which produce soluble carbohydrates, probably mostly in the form of glucose and maltose. Both the soluble carbohydrates already present as well as those produced by amylolytic enzymes furnish food for the yeast in a very suitable form. If flour itself possesses such large diastatic activity that, by digesting it with water a t a suitable temperature, more than one-fifth of its weight is transformed into soluble carbohydrates such as glucose and maltose, the conditions for such transformation deserve careful study. The object of the present investigation was to determin some of the conditions which control the transformation of starch in wheat flour into rqducing sugars. The conditions studied were : optimum temperature; duration of the digestion period; optimum proportion of water and flour; influence of chemicals acting as activators or paralysors. In taking up this work a large number of preliminary trials were made in order to test the best methods of procedure. The results given in the following tables are repetitions of preliminary trials. The following flour grades were used: patent, 80%; straight, 961/2% ; clear, 16l/2%; and low-grade, 3l/2%. These were all made from the same lot of Kansas hard wheat. The straight is simply a blend of the patent and the clear. The lowgrade comes from the mill streams near the tail end of the mill. It contains a much higher percentage of ash and crude fiber than the other flours. The various charges used were based on the content of dry matter. In adding water, that present in the flour was figured in, so as to insure exact uniformity of conditions with respect to the proportion of dry substance and water. Malt extract is used in bread baking for two reasons: The chemical analyses of these flours were as follows: "The Technology of Bread Making," by William Jag0 and William C. Jago.