Book of American Baking / A Practical Guide Covering Various Branches of the Baking Industry, Including Cakes, Buns, and Pastry, Bread Making, Pie Baking, Etc.

by Various

Albuminous substances all contain the four elements—carbon, hydrogen, oxygen and nitrogen, a trace of sulphur, and some contain phosphor.

The difference between these substances and the carbohydrates is that they contain nitrogen. They have also received the name proteids, frequently called flesh formers, on account of their nutritive properties.

Sugar, dextrin and gum carbohydrates that can be extracted with water.

F. Fat contents of flour. Shake vigorously for some time 10 ounces of rye or wheat flour with 40 ounces of ether, to which has been added 40 ounces of pure alcohol. Heat the mixture gently to 104 degrees F., and fat globules will be seen on the surface of the fluid. This is the fat contained in flour. Rye flour contains 2 per cent., wheat flour 1 per cent. of fat.

G. Cellulose in flour. Flour contains more or less fibrin. In order to separate it from the flour, the extractive matters of the flour are washed in consecutive order with water, ether and alcohol, the residue is then boiled in dilute sulphuric acid. The fibrin obtained is then washed and dried. In appearance it looks like wood fiber. This substance is contained also in the gluten and in the envelopes of the starch cells. It is insoluble in water, dilute acids or alkaline. It is indigestible and has no value as a food.

H. Ash of flour. Take a little flour and spread it on a platinum dish and heat over a bunson burner. Continue the heating until nothing remains but a grayish white powder. This is the ash or mineral part of the flour.

These mineral substances enter into the flour through absorption from the earth by the roots of the wheat grass.

The ash of flour is mostly composed of phosphates, and are of great importance because they are bone-forming and help to build up the framework of the human body.

The Average of Analysis.

Separating the various constituents of flour is called the analyzation of flour. If in a different quantity of flour the amount of each component part is determined it is called quantitative analysis. The total amount of all constituents is always figured at 100, in order to give percentage of each constituent contained. Wheat flour contains 13.37 per cent. of water. It means that 100 oz. of flour contains 13.37 per cent. of water. Therefore 100 lbs. of flour contains 13.37 lbs. of water. The same applies to the starch item, 100 oz. of flour contains 69.30 per cent. of starch.