19161 FOODS — HUMAN NUTEITION. 469 



(e. g., 1:99). Furthermore, an appreciable amount of achroodextrin enters 

 the solution with ordinary concentrations of saliva. 



"All of the dextrins under ordinary conditions disappear from the solution 

 within 15 minutes, so that thereafter the further progress of the digestion can 

 be followed by the polariscope, the only optically active substance then present 

 being maltose if maltase has not been added from some outside source. As the 

 amylose is all digested by this time, the further digestion represents action on 

 amylocellulose and amylopectin and their products of hydrolysis. 



"By slow digestion almost the entire amount of amylose present was ob- 

 tained in solution as erythrodextrin at the end of 15 minutes. Hence under 

 ordinary conditions the digestion of amylose must be almost instantaneous. 



" Rose-amylose, derived from amylopectin, digests completely in four hours. 

 This has usually been regarded as the end of starch digestion, the rose-amylose 

 being confused with erythrodextrin. 



"The amylocellulose (cell walls) digests only after more than 24 hours. 



" The only differences observable in the rate of digestion of bread made from 

 hard or soft wheat, and fermented more or less than usual, were due to the 

 relative amounts of gluten present. When the gluten was broken down, the 

 rate of digestion was sensibly the same. 



"The cause of the greater palatability of home-baked bread was not dis- 

 covered. "Various pronounced effects due to fermentation by spoiled yeast were 

 noted. 



" The activity of amylases is not sensitive to small changes of temperature 

 or of acidity produced by the organic acids found in bread ; nor does their 

 activity seem to be proportional to their concentrations. It would seem that 

 imder physiological conditions most of the amylose must be changed to dex- 

 trins in the mouth, and that these dextrins as well as most of the amylopectin 

 and its products of hydrolysis must be digested in the stomach, whereas the 

 digestion of the amylocellulose must take place for the most part in the 

 intestine. 



"Stale (air-dried) bread digests very slowly unless its gluten be completely 

 broken down." 



Milling and baking tests, J. A. Voelckee {Jour. Roy. Agr. Soc. England, 

 76 {1915), pp. 333, 334)- — As a part of the study of the influence of magnesia 

 on wheat, conducted at the Woburn Experimental Station of the Royal Agri- 

 cultural Society, milling and baking tests were made upon four samples of 

 wheat. Two of the samples were raised on new plats of ground and two on old 

 plats, one of each pair of samples being raised on soil to which magnesia had 

 been added. For commercial purposes no differences were noted in the baking 

 quality of the samples. 



Nutrition investigations upon cotton-seed meal, I, Anna E. Richardson 

 and Helen S. Green {Jour. Biol. Chem., 25 {1916), No. 2. pp. 301-318, figs. 5).— 

 Investigating the suitability of cotton-seed meal for human consumption, the 

 authors report in this paper a number of feeding experiments to determine the 

 efficiency of cotton-seed meal as a food for promoting the growth, development, 

 and reproduction of the albino rat. The results indicate that "cotton-seed 

 meal does not contain sufficient minerals for growth, is not actively toxic, con- 

 tains efficient protein, and perhaps fat-soluble growth-promoting substances, 

 similar to those of butter fat but in less adequate quantities." 



Commercial possibilities of the goosefish, H. M. Smith {U. 8. Dept. Com., 

 Bur. Fisheries Econ. Circ. 15 {1914), pp. 5). — It is estimated that the fishermen 

 of the Atlantic coast throw away annually about 10,000,000 of these fish, which, 

 according to analyses of the edible portion, contain more protein than flounders 



