Aluminum-free baking powder is the baking powder that does not contain alum, double-effect non-aluminum baking powder is also non-aluminum baking powder, the general quality of baking powder, mainly to control the speed of gas production is very good, the pre-processing of food production of gas is less, and when the food is heated up to produce a lot of gas. "Double effect" has no practical significance, just manufacturers in order to attract customers to do publicity, any baking powder is the front and the pasta will produce a part of the gas, the back of the heating will produce a large amount of gas, the two gas production is not a double effect?