FOODS— HUMAN NUTRITION. 163 



minute microscopic particles of offal in the products of the lower machines 

 which are not bleached or altered in the process, and which serve the micros- 

 copist as a guide to how the flour has been blended. Examination of com- 

 mercial flours shows clearly that a large number of high-priced flours are such 

 mixtures and could not be sold as such unless previously bleached. 



" Bleaching confers no advantage in nutritive properties or flavor upon the 

 flour, and the large sum spent upon bleaching flour is really a national waste. 



" Bleaching flour with considerable amounts of nitrogen peroxid alters both 

 fats and proteins by nitrating them. Although the changes at the level of 

 commercial bleaching are small, there is no knowledge as to how the small 

 jimounts of organic nitro-bodies formed may affect the human body in prolonged 

 use for years, and as there is no counterbalancing advantage, and an addition 

 also to the price obtained by simulating a superior article, it is suggested 

 either that bleaching should be prohibited, or regulated and notified clearly by 

 label to the purchaser. 



" Bleaching by nitrogen peroxid is not a more rapid achievement of a slowly 

 occurring natural process, but is essentially distinct. For while natural whiten- 

 ing in pure air consists in an oxidation of the colorhig matter, bleaching con- 

 sists in the formation of additional compounds between nitrogen peroxid and 

 the coloring matter." 



The chemical composition of paddy mill products, F. J. Warth and D. B. 

 Daeabsett (Dcpt. Agr. Burma Bui. 10 {1913), pp. 11). — Rice milling is de- 

 scribed and analytical data including mineral constituents reported of the dif- 

 ferent milling products and by-products. Some data are also reported regard- 

 ing pounding rice by hand as compared with commercial milling. The hand 

 process, the authors point out, is clearly wasteful, since none of the hand- 

 milled, broken rice is used for cooking but for cattle food. The marked pref- 

 erence of the natives for the polished rice is commented on. 



According to the authors, " the two foods polished rice and wheat flour may 

 be considered equally good when they form part of a mixed diet in which the 

 extra proteid required is supplied from some other source. Where, however, 

 rice forms the complete diet the nutritive ratio (proteid to carbohydrates) is 

 very low and a small increase in proteids would considerably alter it. It is 

 just possible, therefore, that a part of the ill effects of a diet of polished rice 

 may be due to the very low proteid content. 



" For the rice miller, however, the phosphorus content has become a much 

 more urgent problem since it has been shown that an inadequate supply of this 

 element is a predisposing cause of beri-beri. ... It is important to notice that 

 wheat flour is, if anything, poorer in phosphoric acid than our best polished 

 Rangoon rice. However, wheat flour consumers invariably live on a mixed 

 diet, whilst some rice eaters do not. This explains why no complaint has been 

 raised against the low phosphoric acid content of wheat flour." 



Discussing the matter from the Burmese native standpoint, the authors state 

 that "the more perfect the polish the better does the rice cook, and therefore the 

 preference for highly polished rice is not merely due to its clean white appear- 

 ance but to the good cooking quality indicated by its appearance. 



" It is doubtful whether we have as much reason for preferring white bread 

 as the rice eater has for preferring well polished rice. The question of cooking 

 quality in relation to extent of polishing is one that deserves some study by the 

 millers. It may just be possible to produce a good cooking rice without polish- 

 ing quite as much as is the custom. . . . 



"A chemical test bearing on the question of cooking quality may be men- 

 tioned here. By means of dilute alkali rice grains can be disintegrated and 



