In all our baking, we try to avoid the metallic, soapy taste you sometimes get when you bake with too much baking powder and/or the wrong kind of baking powder.
This article helps you understand the science of why you get this taste.
We always use something that you can buy in health food stores in Italy and is referred to as “Cremor Tartaro” or “natural baking powder”.
It is composed of cream of tartar (potassium bitartrate – a byproduct of the winemaking process), bicarbonate of soda and corn starch, in the following proportion: two parts cream of tartar with one part each baking soda and cornstarch.
We use a little packet of it which weighs 17g (half an ounce) and is enough for 500g (1 lb of flour), but since it does not produce a bitter taste if you use too much, we tend to use the whole packet even for less flour.
You can compose the same by using the following: 1 tablespoon cream of tartar, half tablespoon baking soda and half tablespoon cornstarch. Compose it as and when you need it, not in large batches since it loses effectiveness.
CAUTION: the big disadvantage with using tartrate baking powders is that these create gas quickly when combined with baking soda in the presence of liquid, so the batter must be cooked quickly or it will go flat.
i.e you need to mix your batter and put in in the oven ASAP!