244 ANNUAL OF SCIENTIFIC DISCOVERY. 



mcnts show that it is simply suspended even by the heat required to cook 

 bread thoroughly. Thus, bread made without fermentation, of whole wheaten 

 meal, or of flour in which there is a large proportion of cerealin, will, if kept 

 at a temperature of about seventy-five to eighty-five degrees Fahrenheit, pass 

 rapidly into a state of solution, if the smallest exciting cause be present, such 

 as ptyaline or pepsin, or even that small amount of organic matter which is 

 found in impure water; while the same material, when it has been subjected 

 to the alcoholic fermentation, will not be affected in a like manner. 



The activity of cerealin is very easily destroyed by most acids, also by the 

 presence of alum; and while it is the most active agent known in producing 

 the earlier changes in the constituents of the flour, it cannot produce the 

 alcoholic; but as soon as the alcoholic is superinduced, the cerealin becomes 

 neutralized and ceases to act any longer as a solvent. M. Mouries, taking 

 advantage of this effect of alcoholic fermentation, has adopted a process by 

 which he is enabled to separate from the bran all the cerealin and caseine 

 which are attached to it. He subjects the bran to active alcoholic fermenta- 

 tion, which neutralizes the activity of the cerealin, and at the same time 

 separates t? nutritious matter; and then, having strained this through a fine 

 sieve, he adds it to the white COTIT in the preparation of white bread, by 

 which an economy of ten per cent is effected, and the color of the bread is 

 not injured. 



The peculiar action of cerealin as a special digestive solvent of the con- 

 stituents of the flour gluten and starch has been practically tested by 

 Mr. Darby in a series of careful experiments. He found that when two 

 grains of dry cerealin were added to five hundred grains of white flour, and 

 the whole digested in half an ounce of water at a temperature of ninety 

 degrees for several hours, ten per cent more of the gluten, and about five per 

 cent more of the starch, were dissolved than when the same quantity of flour 

 was subjected to digestion without the addition of cerealin; but in which, 

 of course, there was a small amount of cerealin that is present in all flours. 

 The action of cerealin upon the gluten of wheat is precisely similar to that 

 of pepsin on the fibrine of meat. Pepsin, acting alone on fibrine, dissolves 

 it, but very slowly ; but if lactic acid be added, solution takes place very 

 rapidly. In like manner, the starch present with the gluten of wheat is 

 acted upon by the cerealin, and produces the necessary lactic acid to assist in 

 the solution of the gluten by cerealin. 



With the knowledge thus obtained of the properties of this substance, 

 cerealin, it is not difficult to understand why the administration of bran- 

 tea, with the food of badly-nourished children, produces the remarkable 

 results attributed to it by men both experienced and eminent in the medical 

 profession; and why, also, bread made from whole wheaten -meal, which 

 contains all the cerealin of the grain, should prove so beneficial in some 

 forms of mal-assimilation, notwithstanding the presence of the peculiarly 

 indigestible and irritating substance forming the outer covering of the grain. 



It will be seen that in all the methods of bread-making hitherto adopted, the 

 peculiar solvent properties of this body, cerealin, have been sought to be 

 neutralized simply because it destroys the white color of the bread during 

 the early stages of panary fermentation. It is by thus destroying the activity 

 of the special digestive ferment which nature has supplied for the due 

 assimilation by the economy of the constituents of the wheaten grain, that 

 wheaten bread is rendered incapable of affording that sustenance to the 

 laboring man which the Scotchman obtains from his oatmeal norridge. 



