When confronted with the questions growing out of the use of the various
baking powders now on the market, the puzzled layman is apt to sigh for
the good old days when this product was rather haphazardly mixed at home.
Just in case you run out of baking powder, mix - for each teaspoon of
baking powder called in the recipe ½ teaspoon cream of tartar, 1/3-teaspoon
bicarbonate of soda and 1/8-teaspoon salt. After adding the above ingredients
do not delay in putting the batter into the oven. And don't try to store
this mixture, as it has poor keeping qualities. If you doubt the effectiveness
of any baking powder test by mixing 1 teaspoon of baking powder with 1/3
cup of hot water.
Use the baking powder only if it bubbles enthusiastically. There are
three major kinds of baking powders, and you will find the type carefully
specified on the label. In all of them there must be an acid and an alkaline
material reacting with each other in the presences of moisture to form
a gas carbon dioxide which takes the form of tiny bubbles in the dough
or batter.
In baking, these quickly expand the batter, which is then set by the
heat to make a light textured crumb. Before measuring any of these leavens,
stir and break up any lump, and use a dry measuring spoon. Because of
the decrease in barometric pressure at high altitudes, the carbon dioxide
gas expands more quickly and thus has greater leavening action. For this
reason, the amount of baking powder should be decreased if you are using
a recipe designed for low altitudes.
You may select recipes designed especially for high altitudes. In high
altitudes, baking soda is decreased as for baking powder, above; but in
recipes using sour milk, where it's neutralizing powder is needed, never
reduce soda beyond ½ teaspoon for every cup of sour milk or cream called
for in the recipe.
Tartrate Baking Powder
In these, the soda is combined with tartaric acid or a combination of
cream of tartar and tartaric acid. They are the quickest in reaction time,
giving off carbon dioxide the moment they are combined with liquid. Therefore,
if you are using this kind, be sure to mix the batter quickly and have
the oven preheated so that too much gas does not escape from the dough
before the cells can become heat-hardened in their expanded form. Especially
avoid using tartrate powder for doughs and batters that are to be stored
in the refrigerator or frozen before baking.
Phosphate Baking Powders
These use calcium acid phosphate or sodium acid pyrophosphate, or a combination
of these, as the acid ingredient. They are somewhat slower in reaction
but give up the greater part of their carbon dioxide in the cold dough.
The remainder maybe released when mixture is baked.
Double-Acting or S.A.S BAKING POWDERS
Often referred to as combination, or double acting, baking powders,
these are the baking powders we specify consistently in this book. They
use sodium aluminum sulfate and calcium acid phosphate as the acid ingredients.
They start work in the cold dough, but the great rising impact does
not begin until the dough contacts from the hot oven.
Sodium Bicarbonate or Baking Soda
Used alone, baking soda has no leavening properties. But used in combination
with some acid ingredients such as sour milk or molasses, it gives one
of the very tenderest crumbs. The proportion of baking soda to sour milk
or buttermilk is usually 1-teaspoon soda to 1-cup sour milk or cream reactions.
The reaction of the soda with the acid is essentially the same as that
which takes place when the two ingredients in baking powder meet moisture,
so always mix the baking soda with the dry ingredients first. The acidity
of chocolate, honey or corn syrup is not strong enough to be the only
source of acid, so some recipes with these acid ingredients may call for
both baking powder and baking soda.
If they do use about ½ teaspoon baking soda and ½ teaspoon baking powder
for each 2 cups flour. The small amount of soda is desirable for neutralizing
the acid ingredients in the recipe, while the main leaving action is left
to the baking powder. The amounts of baking powder per cup of flour suggested
above are for low altitudes.
Ammonium Bicarbonate
This forerunner of our modern and more stable leaveners is also known
as powdered baking ammonia, hartshorn. Used for years in Europe to produce
long-lasting crisp cookies, it must be pounded to a fine powder and then
shifted with the dry ingredients or dissolved in a warm liquid such as
water, rum or wine. Substitute it for the baking powder and baking soda
called for in cookie and cake recipes. Buy only small amounts from the
drugstore, as it quickly evaporates if not very tightly contained.
