FOODS HUMAN NUTRITION. 565 



Some additional data are reported regarding the nature of a commercial sub- 

 stance recommended for fumigating flour mills. A chemical analysis showed 

 that this material contained nicotine and other forms of alkaloids. There was 

 no opportunity to determine its efficiency in destroying insects in mills, but 

 the author was " unable to find that it did any injury to the flour. The strong 

 smell of burning tobacco noticeable on the flour did not quickly disappear, and 

 was evident in the bread made from heavily treated flour even 3 weeks after 

 treatment. Otherwise the bread was in every respect equal to that made from 

 the untreated flour." 



Investigations on the effects of bleaching flour are also summarized and dis- 

 cussed. According to the author, the results obtained lead to the belief that 

 " bleaching flour with the oxids of nitrogen produced by the electrical method 

 whitens the flour and slightly improves the texture and appearance of the loaf. 

 This difference is more pronounced with the flour from new wheat than with 

 that from older wheat. The color obtained as a result of the treatment with 

 the gas is whiter, but to many people it is not so desirable as the creamy tint 

 of the normally aged flour. There does not appear to be much difference in the 

 water absorption ; in fact, in all our work we get rather lower absorption. The 

 volume of the loaf is slightly increased, and, naturally, as the bleaching is a 

 process of aging, the increase in volume is most noticeable in the flour from new 

 wheat. To sum up, it would appear that bleaching has some of the effect of 

 time in improving flour, but does not give the full results of ' aging ' produced 

 by time." 



For earlier work see a previous note (E. S. R., 23, p. 368). 



Effect of mill fumigants upon flour, R. Haecourt (Northwest^ Miller, 83 

 (1910), No. 11, pp. 661, 662, figs. 6). — As a contribution to the question of mill 

 fumigation for the destruction of insects the author carried on investigations 

 en the influence of hydrocyanic acid, carbon blsulphid, and sulphur fumes upon 

 the composition and baking quality of flour. 



Treatment with hydrocyanic-acid gas, under the experimental conditions, did 

 not destroy the bread-making quality, while treatment with carbon bisulphid 

 and sulphur fumes resulted in darker loaves, poorer in texture and in general 

 appearance. The author further concludes that treatment with hydrocyanic 

 acid and carbon bisulphid vapor did not materially affect the production of 

 alcohol-soluble or water-soluble proteids, but that in both hard and soft wheat 

 flour the sulphur treatment materially increased the amount of water-soluble 

 proteids. This was especially true of the soft-wheat flour. " The water-solu- 

 ble proteids were also increased slightly by the carbon bisulphid treatment, both 

 in the hard and soft flour, but more particularly in the latter. . . . 



" The acidity of the flours was also influenced, more particularly, as would 

 be expected, by the sulphur fumes, and possibly it is this factor, together with its 

 effects on the gluten, which most seriously injures the sulphur-treated flour." 



The effects of fumigants on the bacteriological life of flour were also studied, 

 hydrocyanic acid showing no reduction in micro-organisms, carbon bisulphid a 

 slight reduction, and sulphur-treated flour a great reduction. 



" From the above results, it is very evident that carbon bisulphid would be 

 very much more injurious to flour than hydrocyanic acid. The results were not 

 continued long enough to ascertain how long the carbon-bisulphid-treated flour 

 would be in getting back to normal condition, but the experiment was discon- 

 tinued because it was felt that, if flour would not become normal in 4 or 5 

 months from time of treatment, it would practically be as fatal to the miller as 

 if it never would regain its original condition. 



