FOODS HUMAN NUTRITION. 165 



STERN (Landiv. Fer.s. Stat., G') (1007), ^0. 5-6, pp. 301-33S).— On an average, 

 table varieties of jiotatoes contained 0.0125 per cent solanin and varieties suit- 

 able for farm animals 0.0058 per cent. The yellow varieties were found to con- 

 tain less than red or blue. In general, the author believes that the more pro- 

 nounced flavor of some varieties of potatoes is due, in part at least, to their 

 higher solanin content. Small or unripe potatoes showed a greater percentage 

 of solanin than full-grown tubers. 



As regards methods of culture, it was found that humus, moisture, and potash 

 tended to diminish the solanin content, while phosphoric acid and nitrogen 

 increased it a little, though the effect of the phosphoric acid was very slight. 

 Potatoes which had turned green owing to exposure to the light contained a 

 considerably higher percentage of solanin than normal potatoes. Rotting neither 

 destroyed nor appreciably diminished the solanin content. 



Studies of the distribution and function of solanin in the potato plant showed 

 that it occurs most abundantly in the growing and sensitive parts, and the 

 author believes that it primarily serves as a plant protector, though it may also 

 play a part in the assimilation of sugai'. 



Properties which determine the quality of wheat, A. Cserhati (Ztschr. 

 Laiidic. Versuclisw. Ostcrr.. D (1906), p. 899; ahs. in Chem. Ztg., 30 (1906), No. 

 102. Rcpert. No. .55, p. .'i62). — Generally speaking, the gluten content of wheat 

 is directly proportional to its protein content, but the proportion of gluten, 

 according to the author, is not a satisfactory measure of the quality of the 

 wheat. 



The proteids of barley, their importance for the valuation of grain, and 

 their relation to the steeliness of the barley, E. Prior (Pure Products, 3 

 (1907), Ao.v. 2, pp. 92-98: 3, pp. I.'i3-l'i6; .',, pp. 192-195; 5, pp. 232-2^2) .—The 

 following are some of the conclusions drawn from the extended series of inves- 

 tigations reported by the author : 



"The content of water-soluble proteids and nitrogenous substances (leucosin, 

 albuinose, etc.) in the barley, and also the edest in-con tent of the barley, bears 

 no fixed relation to the total protein content of the barley, and it varies within 

 comparatively narrow limits. 



" The hordeiu content of the barley and its content of insoluble proteid rises 

 in general with the total protein content, as may be seen from the calculated 

 average values for both proteids ; numerous exceptions are, however, displayed. 



" The amount of hordein -f insoluble proteid in the barley rises and falls 

 naturally with the total protein content of the barley. 



" The percentage composition of the nitrogenous substances of the barley, 

 heretofore designated as total protein, varies greatly and bears no relation to 

 ihe total nitrogen content. . . . 



"The causes of the apparent steeliness (degree of solubility) are the water- 

 soluble, principally colloidal nonnitrogenons and nitrogenous bodies present in 

 the endosperm of the barley, which caulk the starch-converting cells." 



A fermented food made from rye flour, K. Teichert {CentN. Bakt. [etc.^, 

 2. AM.. 17 (niOG), p. 37i;: ahs. in Chem. Ztf/.. 31 (1907), No. 13, Repert. No. 11, 

 p. (i2). — A Polish dish called " zur " is described, which is made by fermenting 

 a rye-flour batter. After fermentation the dough-like material is cooked in hot 

 water. The article includes a study of the bacteria involved. 



The Bambarra groundnut, J. Burtt-Davy (Transvaal Agr. Jour., 5 (1907), 

 No. 18, pp. Ji.'j,3-.'f.~)6). — Analyses of the Bambarra groundnut (Voandseia sub- 

 tcrranca) and other data are quoted. According to the author, these nuts, 

 which are similar to the peanut, though sometimes eaten raw, are usually boiled 

 in two or three waters before they are eaten. 



