Flour is divided into ultra-high gluten flour, high gluten flour, medium gluten flour and low gluten flour; 1. Ultra-high gluten flour: protein content is more than 14%, and it is gluten-free, suitable for products such as spring rolled skin. 2. High-gluten flour: The protein content is above 12.5%, and the grain is coarse, so it is suitable for making flour food (bread) or fried food (fried dough sticks), also known as bread flour. 3. Medium gluten flour: the most commonly used flour, also known as multi-use flour. Protein content is 9%- 1 1%, which is suitable for making noodles, jiaozi, steamed buns and steamed buns. 4. Low-gluten flour-The content of protein is above 7.5%, with fine and soft particles, which is suitable for cakes, biscuits, western pastry and other foods, also known as cake powder.