1, put baking soda when kneading dough. The proportion of baking soda powder should not exceed "five thousandths", that is, the proportion of 2 kilograms of free baking soda should not easily exceed 5 grams, otherwise the food will be black in color and bitter in taste.

At 2.50℃, baking soda gradually decomposes into sodium carbonate, water and carbon dioxide gas, and completely decomposes at 270℃. Therefore, if baking soda is dissolved before use, hot water must be used, but the water temperature should not be too high, otherwise baking soda will be ineffective.