Hercules® Double is a high quality baking powder, with dual action gas release. Calcium releases gas quickly to nucleate and stabilise the batter. This leaves the slow acting SAPP to control the release of gas during preparation and baking, for controlled volume. Particularly suitable for craft bakery lines, speciality breads, pizza and naan On the other hand, double-acting baking powder contains more than 1 type of acid. To be more precise, it contains two types of acids. Another difference is that these acids have different reaction times. Individuals rarely use the standard baking powder. But it is common among manufacturers who bake items on a large scale. eLSWnZp.