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Laboratory Exercises (Lb bicarbonate of soda lb)
lb. bicarbonate of soda 1 1/8 lb. cream of tartar 4 oz. cornstarch 1. Mix soda and cornstarch together and sift three or four times in a fine flour sieve. 2. Add the cream of tartar and sift seven or eight times. Put into Mason jars and screw the covers down tightly. (Always keep the baking powder can tightly covered to prevent the baking powder losing strength.) Ginger Bread. 2 1/4 C. flour 1 t. soda 1½ t. ginger t. salt 1 C. molasses C. boiling water 1 egg 4 T. melted butter 1. Mix and sift dry ingredients. 2. Add boiling water to the molasses and stir into the dry ingredients. 3. Add well beaten egg and melted butter. Beat well. 4. Pour into a buttered shallow pan and bake about 25 min. in a moderate oven. If the bottom of the pan is lined with a sheet of buttered paper, the ginger bread will be less apt to burn on the bottom.
Note. This recipe may be made without the egg.
Ginger Drops.
Two entries from a cookery laboratory course: a homemade baking powder and a molasses gingerbread that uses soda alone rather than the powder. Several of the quantities as printed have lost their fractions, so treat the proportions below as guidance rather than transcription.
- Baking powder proportionsA common cream-of-tartar formula of this period runs roughly two parts cream of tartar to one part bicarbonate of soda, with starch added; the proportion of starch varies between manuals. The figures as printed here are incomplete and should not be scaled up blind.
- Why the cornstarchChiefly a desiccant, keeping the soda and acid dry so they do not react in the jar; it also dilutes the mixture to a standard strength. Repeated sifting is what distributes it evenly; the seven or eight siftings called for are not excessive.
- Cream of tartar powder is single-actingIt releases its gas the moment liquid is added, unlike modern double-acting powders which hold a second reaction for the oven heat. Batters made with it must go into the oven at once, and it is not interchangeable spoon-for-spoon with commercial powder.
- StorageMason jars with screwed lids remain the right answer. Homemade powder loses strength faster than commercial; test a half teaspoon in hot water and discard it if it does not fizz vigorously.
- Moderate oven350F. A shallow pan of gingerbread that size takes 25 to 30 minutes; test with a skewer at the centre rather than by colour, since molasses browns early.
- The molasses and sodaSoda here is raised by the acidity of the molasses, so the amount is matched to it. Modern table syrups are generally milder than the unrefined molasses of the period, so a robust unsulphured molasses is likely to give a nearer result than a light syrup.
- Boiling water into the molassesThis thins the molasses so it combines easily with the dry ingredients, and warms the batter so the soda starts working immediately. Have the pan buttered and the oven up to heat before you combine them.
- Lining the panThe buttered paper is sound advice and parchment does the job better. Sugar-heavy molasses batters scorch on the base long before the centre sets.
- YieldThe recipe specifies only a shallow pan; no size or number of portions is given.
Manuals like this one taught baking powder as a chemistry lesson before they taught it as a shopping item. Cream of tartar, a by-product of winemaking scraped from the inside of the cask, was the household acid of choice from the mid-nineteenth century, and mixing your own powder let a domestic-science class demonstrate exactly what commercial tins contained at a time when adulteration with alum was a live public controversy. The gingerbread that follows belongs to an older tradition still: molasses cakes leavened by the reaction between soda and the acid in unrefined sugar syrup, a method that predates purchased baking powder entirely and survived alongside it because the flavour of the two is not the same.