What is the difference between starch and flour?

Many people easily confuse starch and flour. In fact, these are two completely different substances, both in terms of composition and function. Starch is a polysaccharide, while flour is rich in protein, fat and dietary fiber. Starch is only a small part of flour.

1. Nature

Flour is a powder made by directly grinding wheat or other grains after peeling; starch is a polysaccharide obtained by separating protein and other substances from flour. It is insoluble in water and will absorb water and swell in hot water to become a viscous, translucent colloidal solution.

2. Ingredients

Flour is rich in protein, fat, carbohydrates and dietary fiber, and is sweet and cool in nature. It has the effects of nourishing the heart and kidneys, strengthening the spleen and intestines, and removing heat and quenching thirst. Starch is a part of flour, and its main components are more than 80% carbohydrates and more than 10% water.

3. Feel

We can dip our fingers in some flour and then rub them with our fingers. You will find that it is very smooth, but it is not like this for starch. It will feel astringent. The feeling is somewhat similar to rubbing lotus root powder, but it is more difficult to rub.

4. Appearance

Compared with starch, flour is slightly yellow; starch is very white and purer in color.

5. Cooking

Flour is mainly used to make steamed buns and for frying (youtiao, pork tenderloin, KFC fried wings, etc.); starch is generally used to make soup. Soups made with starch, such as seaweed egg drop soup, are clear and sticky, with good taste and appearance.

6. Function

Starch has a strong gelatinizing effect and hangs on the surface of food during cooking, which can protect the nutrition and taste of the food inside; flour cannot play a protective role because of the protein it contains.

7. Application

We know that flour has a wide range of uses. After thickening the food, it can also be used to make steamed buns, bread and other foods we eat every day. However, cornstarch, or starch, has fewer uses.