776 DISCUSSION ON WHEAT: 
wheat extracted as germ by either process is very small, but as a consequence 
enzymic action is diminished to an appreciable extent. Some harm is also 
done to flavour, but, on the whole, it is desirable to extract the germ. 
Enzymic action depends not only upon the presence of enzymes in sufficient 
quantity but upon the physical state of their pabulum. The methods of 
milling, in particular the skilful use of water in conditioning the wheat 
before grinding or in the processes of grinding and separating, or even the 
addition of water by the miller to certain flours after milling, may 
materially assist enzymic action. 
Colowr.—Opinions differ as to whether perfection of colour implies 
whiteness of chalky or of creamy hue; all are agreed it should imply 
brightness of appearance in crumb and crust. Excellence of colour in 
bread cannot be measured by any absolute colour standard. It is largely 
a question of optics. Refraction and reflection of light most materially 
affect the judgment of the observer in looking at a loaf of bread. A flour 
which is white or even very white but weak may make puddings of good 
colour, but loaves of poor dingy appearance. However, if an improved 
aeration be effected, either by successful treatment of the flour by the miller 
or baker or even by the admixture of some stronger darker flour, the 
resulting bread is made to appear much whiter. The causes which affect 
colour in flour do not seem to have been definitely determined. Modern 
developments of flour milling have eliminated dirt and dark fungoid con- 
tamination and in increasing degree are still diminishing the amount and 
intensity of friction in milling, whereby discoloration due to the pulveris- 
ing of the husk is diminished. It is desirable to obtain a more thorough 
acquaintance with the colouring matter of wheat and flour to know with 
more precision what it is, how it is distributed by Nature in wheat and 
what happens to it in milling. 
Scientific and milling circles have been much exercised as to whether 
artificial bleaching of flour is due to nitrating or oxidising or to both. 
Chemists should consider the point why the addition of alkali turns some 
flours yellow and why the addition of acid or acid salts has sometimes a 
whitening effect. 
Cerealists and chemists might jointly consider whether it is a fact that 
climate materially affects the colour of wheat; for instance, whether a red- 
skinned wheat grown in California does in fact become white-skinned after 
a few seasons there, and if so what change has been effected in the nature 
and distribution in the berry of the colouring matter. 
Strength (Size and Shape of Loaf).—In most cases a large loaf is an 
indication of the high gas-yielding capacity of the flour from which it is 
made, and is ordinarily also an indication of high diastatic power. A 2-lb. 
loaf measuring 3000 c.c. is better aerated than one measuring 2,200 c.c., 
and is therefore more likely to be digested easily. A flour from which large 
shapely loaves can be made probably contains more nitrogenous matter than 
a weak flour and is therefore more highly esteemed from the dietetic point 
of view: The effect of these considerations in the commercial world is to 
cause a demand for strong flours and wheats, and as ordinarily there is a 
larger supply of weak wheats than of strong, the latter realise a higher 
price than the former. It has therefore become important to ascertain the 
ultimate cause of strength from the chemist’s point of view, also to ascertain 
whether the potential strength of any flour or wheat has been developed or 
utilised to maximum advantage. It has recently been stated or suggested 
that the quantity of gas given off in fermentation is either the direct cause 
of strength or is to be correlated with it. That proposition is untenable. 
A very large proportion of the gas evolved in panary fermentation is lost, 
either as a result of the mechanical handling of the dough or by gradual 
diffusion. The leak is not the same in the cases of all flours, and it was 
