THE VITAMINE CONTENT OF MAIZE AND MAIZE- 

 MILLING PRODUCTS, AND THE AMBIGUITY OF 

 ITS CORRELATION WITH THE PHOSPHORIC 

 OXIDE CONTENT. 



By Henry Hamilton Green, D.Sc, F.C.S. 



(Abstract.) 



{Printed in the Annual Report of Director of Veterinary 



Research, Pretoria.) 



The examination of maize-millino- products by dietetic ex- 

 periments, using the pigeon as discriminant, indicates that the 

 distribution of vitamine in the maize kernel follows the distribu- 

 tion of phosphoric oxide whenever any given sample of grain 

 is taken into consideration. This parallelism, however, does not 

 hold between different samples of grain, and in a series of 

 samples oif whole maize varying in P, O^ content from 0.35 per 

 cent, to 0.71 per cent, no difference in vitamine content could 

 be detected by pigeon analysis. In these samples the " indicator 

 limit " of phosphoric oxide, for milled meals on the border-line 

 of efficiency, would vary from 0.23 per cent, to 0.46 per cent. 

 It is therefore impossible to use phosphoric oxide in milled pro- 

 ducts as indicator of vitamine efficiency unless the phosphoric 

 oxide content of the original mother-grain is known. This 

 information is rarely available, and the determination of Po O5 

 as a general analytical guide to efficiency, as advocated by 

 Voegtlin, Sullivan, and Myers, is therefore ruled out of court. 

 Their standard of 0.5 per cent. Pa Og for maize flour would 

 condemn more samples than it passed, and w'ould condemn the 

 majority of perfectly efficient South African meals. Simple 

 microscopic examination of a meal, to gauge the extent of 

 milling, would be a safer guide than the Po O., standard. 



By taking "' average pigeon requirements " as standard for 

 comparison, and stating this as 100, it is possible to assign 

 " vitamine indices " to any given diet. On this basis whole 

 maize works out at about 160 to 180 — i.e., contains over 60 per 

 cent, more vitamine than is actually required in metabolism — 

 and whole maize can thereifore stand depletion of vitamine (or 

 P., 0-) to the extent of about one-third before deficiency is 

 likely to be manifested. The following \itamine indices repre- 

 sent determinations on an average series of milling products to 

 an estimated accuracy of about to per cent, either w^ay : — 



Whole Fine Hominy 



Product : Maize. Meal. Seconds. Bran. Chop. Samp. 



Vitamine Index 160 120 170 180 380 30 



The actual value in any given case depends, of course, upon 

 the mode of milling. The average fine meal is not deficient. 

 The more highly milled high-class table products and breakfast 

 foods (Fanko, etc.). are almost invariably highly deficient, and 



