THE “RISING” AGENT

Greymouth Evening Star, 16 June 1936, Page 9

THE “RISING” AGENT

HOW BAKING POWDER BEGAN. The modern cook does not worry about the leavening agent when she makes a line cake. She simply opens a tin of baking powder, measures out the required amount, and is confident that the cake will be light and fluffy. For tlie manufacturers of baking powder know their business. But. if the cake baker of to-day should examine recipes in cookbooks published GO or more years ago, she would be surprised to find that the word “baking powder” is not even mentioned. The reason is obvious: baking powder was unknown. Our ancestors had to resort to other leavening agents to raise their batters, says a- writer in the “Christian Science .Monitor.”

Eggs have always been used as leavening agents, but before the time of baking powder it was. necessary to use 1" to 12 of them for even the simplest cake. It was also necessary to beat the eggs long and vigorously in order to incorporate enough air in them.

Eggs were used for line cakes, but the first all-purpose leavening agent was pearl-ash (potassium carbonate). 'lhis product, the early housewife distilled from wood ashes. Pearl-ash, being an alkali, could only be used with sour milk, molasses, or when some other acid substance such as vinegar, aitim or hydrochloric acid was added to the batter.

The combination of alkali and acid produced the chemical reaction, a reaction which liberated the gas (carbon dioxitie) to raise the batter, but which left a potassium salt as a residue. This residue often made the product very unpalatable, especially if the wrong proportion of alkali and acid was used.

Amomnia was also used for an alkaline reagent. In the old days ammonia was called hartshorn. There was the same hazard of wrong proportion as in the other mixtures, and many bakers, it is said, sold biscuits that smelled of ammonia, because of carelessness in measuring the two reagents. It was a great step up for the housekeeper when she could purchase saleratus from the neighbouring chemist. At first, saleratus was a carbonate of potash, but later sodium was substituted for potash. Like the pearl-ash and ammonia, saleratus must be used with an acid in the right proportion to neutralise the resulting salt. The yellow biscuits that cur grandmothers sometimes served testified to a salt that was anything but neutral. At the present time the commercial name for saleratus is soda, and it is a more refined product.

Another step in the evolution of leavening agents was the use of cream of tartar as an acid medium for the soda. Cream of tartar is by far the most satisfactory acid for fine cakes. It is insoluble in cold liquids, and Rochelle salt —the derivative of soda and cream of tartar —leaves no taste in the cake. Two parts of cream of tartar to one of soda is the correct proportion. There are cooks at the present time who use this combination for a leavening agent. But for the modern housewife to mix cream of tartar and soda means a great waste of time as the baking powders, sold in every grocery store, are simply these two agents, mixed by weight, in the right proportion, and ready for use in convenient form.