Sodium bicarbonate, also known as baking soda, mainly decomposes itself to produce carbon dioxide gas when heated. The expansion speed of baking soda powder in cakes is slow, and the structure of products is relatively uniform. Sodium carbonate, an alkaline substance, remains after the decomposition of baking soda, which deepens the internal color of the product, which is the biggest disadvantage of baking soda. If the acidity of dough is high, baking soda will also react with some acids to produce carbon dioxide gas. Ammonium bicarbonate turned into smelly powder again, big screwdriver. Its mechanism of action is the same as baking soda. After decomposition, a large amount of gas is produced, which makes the baked food fluffy. However, it is also easy to cause the structure of the product to be too loose or there are large holes on the surface, which will lead to the collapse of the product. Moreover, it will produce a strong irritating ammonia smell during heating, which will affect the quality and flavor of food. When combined with soda, it is generally not used alone, and the dosage is strictly controlled. Baking powder is also called baking powder. Baking powder is actually a compound loosening agent, which is mainly composed of alkaline substances, acidic salts and fillers. When baking powder is used in pastry making, the product has uniform texture, fine texture, no big holes and normal color. Widely used in the production process, the dosage is 1% to 3% of flour.