THE BAKERS GUIDE

The same method is applied to the estimation of ginger, finnamon, aromatic essences and waters t cochineal, carmine, etc., using suitable standards for each substance.

Flour and Bread.— Weigh i gram of flour and place it in a small mortar, add a teaspoonful of water and triturate it diligently for one minute with the pestle, now add four ceniims of solution of potash (official liquor potassae), mix well for 20 seconds, and add water gradually to a hundred centims, so as to make a 1 per cent, mixture of flour.

The flour is then estimated as ah albuminous mixture or •solution. For such weak albuminous solutions the constant dividend is three and a half instead of four. The calculation, always simple, is further simplified by using a table referable to the results obtained by the subnorme. Suppose the routine 1 per cent, flour mixture is used, the constant dividend for subnorme is seventy (7 by 100), and the quotient is the percentage of total albuminoids in the flour. The four centims of liquor potassae would be sufficient for a food-stuff containing 50 per cent, of albuminoids.

Table fori per cent. Flour Mixtures; Referable to the Subnorme.

Centims Decolourising Subnorme. Percentage of Albuminoids.

Ginger. — A gram of good ginger was made into a decimal tincture with rectified spirit, i.e., the ginger was extracted com- pletely. One centim of this decimal extract of ginger was diluted with water to 10 centims so as to represent a 1 per cent, solution of ginger.

Of this centesimal solution 3*6 centims decolourised the sub- norme or eighteen centims the norme. Hence the constant dividend for ginger is eighteen, the divisor is the centims de- colourising the norme, and the quotient is the percentage of ginger.

Digitized by