THE BLEACHED FLOUR DECISION 



May I be permitted to answer the editorial signed " M. C," on 

 "The Bleached Flour Decision," which appeared in the April issue 

 of the BiocHEMicAL Bulletin (p. 487) ? 



While I was associated with Professor Alway, at the Nebraska 

 State Experiment Station, we had occasion to spend the greater part 

 of a year investigating the subject of the bleaching of flours by the 

 Alsop process, i. e., the use of nitrogen peroxide.^ 



At the Start I may State that the work was not done under any 

 grant from the miliers, or others interested in the process, but was 

 under a grant from the Adams Fund ; and that all conclusions were 

 based solely upon the experimental evidence. I may also add that 

 at this time I have no interest in the matter except to see that facts 

 are stated. 



I. The "poison" to which " M. C." refers is the nitrite-reacting 

 substance (NaNOg ?) which is present in bleached flours and gives 

 the reaction with the Griess-Ilosvay reagent. This "poison" is 

 present in bleached flours not to exceed 6-10 parts per million, and 

 usually in much smaller quantities. A greater proportion may be 

 introduced by "over bleaching," but in over bleached flours a dirty 

 yellow color is produced and the flour is ruined commercially. 



When a flour which has been bleached is baked, all, or nearly all, 

 of the nitrite-reacting substance is destroyed, and it very rarely 

 happens that loaves of hread made from bleached flours and un- 

 bleached flours can be distingiiished from each other by the nitrite 

 test. .This is especially true if the baking has been done in a gas- 

 fired Oven, for under such conditions bread made from unbleached 

 flour will give the nitrite test. 



Aside from the nitrite test, there is only one other distinguishing 

 feature, since the baking quality of the flour, the expansion of the 

 gluten, and the odor, taste, weight, lightness, and texture of the 



1 See Bull. No. 102, Nebr. Agric. Exper. Sta. (The Effect of Bleaching upon 

 the Quality of Wheat Flour). 



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