According to performance and use, it is divided into: special flour (such as bread flour, dumpling flour, biscuit flour, etc.), general-purpose flour (such as standard flour, rich and strong flour), nutritionally fortified flour (such as calcium-enhanced flour, rich flour, etc.) Iron flour, "7+1" nutritional fortified flour, etc.).

According to accuracy, it is divided into: special first-class flour, special second-class flour, standard flour, ordinary flour, etc.

Floors are classified according to their protein content

1. High-gluten flour High-gluten flour, also known as strong-gluten flour, has high protein and gluten content. The protein content is 12-15, and the wet gluten value is above 35. The best bread flour is Canadian spring wheat flour. High-gluten flour is suitable for making bread, puff pastry, puff pastry, etc.

2. Low-gluten flour Low-gluten flour, also known as weak-gluten flour, has low protein and gluten content. The protein content is 7-9, and the wet gluten value is below 25. British, French and German weak flours all fall into this category. Low-gluten flour is suitable for making cakes, sweet pastries, biscuits, etc.

3. All-purpose flour All-purpose flour is a type of flour between high-gluten flour and low-gluten flour. The protein content is 9----11, and the wet gluten value is 25----35. Common flours such as winter wheat flour produced in the United States and Australia and standard flour in my country belong to this type of flour. All-purpose flour is used to make heavy fruit cakes, meat pies, etc.

In the simplest terms, the main ingredient of cornstarch is starch. In addition to starch, flour also contains gluten. If the gluten in the flour is extracted, what is left is starch, which is wheat. Starch.

Almost all cornstarches are products that are precipitated, dried, and pulverized in water after processing. It is precisely because of this that the scientific name of cornstarch is starch. There is no water involved in the entire flour processing process, only the grinding and sifting process.

Experienced people can tell whether it contains cornstarch or flour by touching it with their hands. Cornstarch will make a squeaking sound when crushed by hand, but flour will not.

The reason why cornstarch is used instead of flour for sizing when cooking is because:

1. Cornstarch will quickly sink to the bottom in water and become water starch, which will easily adhere evenly when used. Wrapped on the surface of the raw materials, it can well protect the internal moisture of the raw materials during cooking, thereby achieving the purpose of making the raw materials tender.

2. Contrary to cornstarch, flour does not sink easily to the bottom of the water. When sizing, it cannot or is not easy to coat the raw materials evenly due to the presence of gluten, so flour is not suitable for sizing in cooking. use.

3. The transparency of cornstarch after gelatinization is much better than that of flour, which can increase the luster of dishes, while flour cannot meet this requirement.

4. The time for flour to be hydrolyzed after gelatinization is shorter than that of cornstarch. Water will flow out after being left for a while, while cornstarch needs to be left for much longer.

These may be the reasons why no one is willing to use flour to replace cornstarch in cooking.