Difference between starch and flour

Starch is a substance composed of glucose molecules. It is a component of food ingredients and is mainly found in wheat. It is also a component of flour. Flour is a powder ground from wheat. It contains starch, trace elements and other ingredients. The two are completely different and it is easy to tell them apart because flour is visible and starch is invisible. We can judge from this aspect.

The concept of starch:

The starch used for thickening is also called dough flour. Various starches are polysaccharide polymers formed by the condensation of multiple glucose molecules.

The starches used for cooking mainly include mung bean starch, tapioca starch, sweet potato starch, sweet potato starch, potato starch, wheat starch, water chestnut starch, lotus root starch, corn starch, etc. Starch is insoluble in water. When heated with water to about 60°C (different types of starch have different gelatinization temperatures), it gelatinizes into a colloidal solution. Thickening sauce utilizes this property of starch.

The concept of flour:

Flour is made from wheat. Names such as high-gluten wheat flour refer to the flour we use in daily life. It can be divided into high-gluten flour, medium-gluten flour, low-gluten flour and gluten-free flour.

So, from the concepts of starch and flour, we know that starch is not flour.

The difference between starch and 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. Appearance

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

4. Feel

If you dip your fingers in a little flour and rub it, it will be very smooth; while starch will feel astringent, and the feeling of rubbing starch with your hands is very similar to the feeling of rubbing lotus root powder with your fingers. When rubbing it, it feels like somersaults.

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

Flour has a wider range of uses. In addition to thickening, it can also be used to make a variety of foods such as slender noodles, steamed buns, bread, etc.; while starch, relatively speaking, has more limited uses.