The chemistry of wheat, flour and bread and technology of breadmaking / by William Jago.
- William Jago
- Date:
- 1886
Licence: Public Domain Mark
Credit: The chemistry of wheat, flour and bread and technology of breadmaking / by William Jago. Source: Wellcome Collection.
87/538
![MINERAL MATTERS. CHAPTER Y. CONSTITUENTS OF WHEAT AND FLOUR. MINERAL AND FATTY MATTERS. 111. Construction of Wheat Grain.—Having given a brief outline of the principles and theory of Chemistry, in so far as they are more or less connected with the present subject, our next object must be to describe the chemical properties of the different compounds found in the grain, and to trace them out in the history of the flour and offal. The “ Cereals,” to which wheat belongs, is the name given to the grasses which have been cultivated for use as food. The grain, as is of course well known, is the seed of the plant ] although not strictly chemical it will be well to give here a short description of its various parts. The most impoi-tant portion of the seed is the embryo or germ ; this, which is a body rich in fatty matters, is that part of the seed which grows into the future plant. The interior of the seed contains a quantity of starch and other compounds, designed for the nutrition of the young plant when growing. The whole is enclosed in an envelope, made up princi- pally of woody fibre, and arranged in a series of coats, one outside the other, somewhat like those of an onion, only on a much finer scale. During the process of milling, the grain is divided into flour and what is technically known as offal. This latter substance, or group of sub- stances, includes the germ, bran, pollard, &c. The bran and pollard are the different skins of the grain broken up into fragments of various sizes. This department of the subject will be dealt with fully in a sub- sequent part of the work. 112. Constituents of Wheat.—A large number of chemical compounds may be obtained from grain : these naturally divide them- selves into Mineral or Inorganic Constituents, and Organic Constituents. The inorganic portions of wheat consist of water and the mineral bodies found in the ash. The organic compounds may be conveniently grouped into—fatty matters, starch, and allied bodies having a similar chemical composition, and nitrogenous bodies or albuminoids. Of these sub- stances the fats have the simplest composition, next come the starchy bodies, and lastly, the albuminoids, whose constitution is extremely complex. It may be stated as a general rule that the more complicated the constitution of a body, the more easily is it broken up into simpler compounds: this holds good in the case at present under consideration. The fats are not liable to undergo any very radical alteration in chemical constitution ; starch changes more readily, while the albuminoids under favourable circumstances decompose with great rapidity.](https://iiif.wellcomecollection.org/image/b28125848_0087.jp2/full/800%2C/0/default.jpg)
