FOODS^ — HUMAN KUTElWON. 161 



"One difficulty in judging color is to distinguish true color from the color 

 appearance as influenced by texture. The desired color is white with a deli- 

 cate creamy tint. ... A yellow tint is much less objectionable than a grayish 

 tint or a chalky white. The yellow is due to the color inherent in the wheat 

 kernel, while a grayish tint shows faulty cleaning of the wheat or imperfect 

 dressing of the flour." 



The third part of the bulletin presents the results of a study of the chemical 

 composition and baking qualities of 19 flours from a four-break mill, and 26 

 samples from a five-break mill. 



In the chemical analyses of the commercial flours and of the samples from 

 the two mill streams, determinations were made of ash, protein, gliadin, gluten, 

 acidity, total and water-soluble phosphorus, and of hygroscopic moisture. It 

 was found that a definite relationship existed between the acidity and phos- 

 phorus content, that the variation in the moisture content of the flour was more 

 affected by the water used in tempering than by a variation of the moisture 

 originallj' present in the wheat, and that the protein content of the flour de- 

 pended upon that originally present in the grain and on the method of milling. 



" That the proteins of a wheat flour strongly influence the baking qualities 

 of the same is undoubtedly true, but the question is more complex than merely 

 ascertaining the ratio between gliadin and the rest of the proteins. . . . The 

 other proteins may have as much to do with the baking qualities as gliadin, 

 and it is not only the proteins present in the sound wheat kernel which deter- 

 mine the baking qualities, but also the protein decomposition products. . . . 



" The short patent has the lowest per cent of ash, while the low grade has 

 the highest. The ash content is lowest in those streams which come from the 

 interior of the kernel, while it is highest in those streams which are taken 

 from that portion next the brsn. . . . 



" The protein content follows almost the same law of variation as the ash. . . . 



" There is a gradual increase in acidity in the flour streams in proportion 

 as they contain material next to the bran. . . . 



" The percentage of ash furnishes a very good indication in regard to the 

 quality of a flour as far as that is related to the method of milling . . . the 

 feed contains ten times as high percentage of ash as the flour. Consequently, 

 the presence of fibrous materials in the lower mill streams influences the ash 

 content more than any other factor. The composition of the ash is also im- 

 portant in judging the baking qualities of a flour. . . . 



" The patent has a lower percentage of protein than the wheat, while both 

 the clear flours and the low-grade flours have a higher percentage. The break 

 flours have a regular increase in protein percentage corresponding to the 

 break number, the fifth break being the highest in percentage of protein in all 

 these flours, while the bran-duster flour and the fourth break have the next 

 highest percentages. In the middlings there is almost the same regular in- 

 crease in protein content corresponding with the number of reductions." 



In the fourth part of the publication is considered the effect of storage upon 

 flour as determined by chemical analyses and baking tests. The work, which 

 extended over two seasons with bleached and unbleached flours stored in a 

 steam-heated room, a nonheated room, and in sealed cans, showed that on 

 storage flours may lose 2 per cent of their original weight, the loss being mostly 

 one of hygroscopic water. The chemical composition and baking quality are 

 otherwise very little affected by storage. 



[Wheat and flour analysis] (Ann. Rpt. Dept. Agr. and Stock {Queensland'], 

 1913-14, pp. 100-107, pis. 2). — The results are given of chemical analyses and 

 the grading of a number of samples of wheat and wheat flour. The samples 



