Plants of three hard red winter wheat varieties differing in their resistance to attack by hessian fly (Muyctrola destvuctor Say) were compared a t the fourth leaf stage for their content of constituents extractable by 80% ethanol. Eleven amino-acids, five organic acids and two inorganic acids were identified. Seven sugars were separated, two of which were unidentified polysaccharides. The main difference was that the susceptible variety (Tenmarq) contained allulose, or allulose in combination with some other component. This compound was present to a lesser extent in the semi-resistant variety (Ponca) and not present in the plants of the resistant variety (C.I. 12855). Sorbitol also was found in Tenmarq but not in the other varieties.

Attack by Sitodiplosis mosellana decreased germination capacity, bushel weight and flour yield of wheat. The ash of the flour increased slightly and its maltose and colour grade values increased greatIy. a-Amylase and protease increased only in proportion t o the decrease of kernel weight and was not related to the extremely large increase in number of fungi and bacteria occurring on and in attacked grains.The water absorption, Extensometer resistance and Extensometer extensibility values all decreased greatly in doughs made from flour milled from attacked grain. The loaves made from such flour were inferior to others in outside colour, nature of the crumb, and loaf volume. Blending the flour milled from attacked grain with flour from a good-quality wheat lowered the bread-making quality of the latter.Experimental evidence indicated that increased a-amylase and protease activities were not the causes of the poor quality of infested grain, which seem likely to result from the failure of protein to develop properly.

The literature on the role of chlorine treatment of flour for use in high-ratio cake production is discussed in relation to current knowledge of cereal chemistry and cake technology. A brief perspective of the present use of chlorine in high-ratio cake flours is included. Investigations of the uptake of gaseous chlorine by flour and its distribution among and chemical action upon the major flour components (water, protein, lipid, and carbohydrate) are assessed. The physical effects of chlorination as demonstrated by experiments with batters and cakes and by physicochemical observations of flour and its fractions are also considered. The characteristics of the starch in flour appear to be critical in high-ratio cakes. Chlorine treatment modifies the gelatinization behavior of the starch granules yet does not change their gelatinization temperature not is there evidence of chemical attack upon the starch molecules. Therefore, it is suggested that chlorine effects the necessary changes in starch behavior by reacting with the noncarbohydrate surface contaminants on the granules. Alternative methods of improving high-ratio cake flours are mentioned, particularly heat-treatment processes.

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