Is lotus root starch a healthy food? How did lotus root starch become a bowl of paste?

Lotus root powder is crystal clear, delicate, fragrant, mellow and sweet. In history, it was served as "tribute powder" to the royal family. Yao Siqin, a poet from Qiantang in the Qing Dynasty, wrote a poem called "Lotus Root Powder": "Who grinds it into jade, dripping fragrant liquid around the mill? It is not stained by mud, but how can it be too white when stained with powder? Spread the box in the autumn sun, and paint the pieces with silver knives. A pinch of it is added to the soup, and the rhinoceros spoon is slippery and smooth."

Although lotus root starch is good, making lotus root starch is a technical job. I believe many people have experienced failure in making it. Why is it so difficult to make lotus root starch? How is it made?

Is lotus root powder a healthy food?

When it comes to lotus root powder, we have to first talk about the raw material lotus root. Lotus root is rich in nutrients, and the vitamin C content is as high as 50-60mg/100g, which is comparable to many fruits. At the same time, lotus root contains minerals such as calcium and potassium. Not only that, the total dietary fiber of lotus root can almost reach 30%, most of which is soluble dietary fiber. Soluble dietary fiber has strong water absorption, which can increase satiety and promote intestinal peristalsis.

Lotus root powder is mainly starch extracted from lotus root, and its nutritional value is definitely lost compared to lotus root. Although the main ingredient is starch, pure lotus root powder is a low GI food, and its glycemic index is not high, so diabetics can eat it in small amounts. This is because lotus root powder contains a certain proportion of resistant starch, which can stabilize postprandial blood sugar levels to a certain extent, and is also good for intestinal health.

Image source: Tuchong Creative

However, it should be noted that since pure lotus root powder has a relatively light taste, a lot of sugar is added to many commercially available instant lotus root powders. Therefore, you need to pay attention to the ingredient list when purchasing to avoid excessive sugar intake.

The production process of lotus root powder

Lotus root starch is a snack made from lotus roots. The traditional method of making lotus root starch includes selecting lotus roots, grinding, washing, bleaching, draining and roasting.

Select lotus root

The scorching sun makes the summer scenery of West Lake in Hangzhou beautiful, just as the poem says: "The lotus leaves are endless and green, and the lotus flowers are red in the sun." However, the lotus roots are too watery and brittle at this time, so it is not the best time to pick them. When autumn comes, the starch accumulation of the lotus roots increases and the water content decreases, turning them into "fresh old lotus roots" and they can be picked.

2. Refining

Wash the lotus root, remove the nodes and peel it, then put it into a mortar or grinding bowl and grind it. Add appropriate amount of water and mix it with the lotus root to make lotus root paste.

3. Washing pulp

Put the ground lotus root paste into a clean cloth bag, place a container underneath, squeeze the cloth bag hard, then pour clean water into the cloth bag and stir continuously until clean water is filtered out.

4. Pulp bleaching

Let the filtered lotus root pulp stand for 1-2 days, stirring it once a day. After stratification, filter out the broken lotus root residue floating on top and pour out the clear liquid above. Continue to add water to dilute the sediment at the bottom and let it stand. Repeat the sedimentation until the lotus root powder becomes white.

Drain and Roast

After the lotus root powder has been allowed to settle, it is hung up in a cloth bag to drain the water, then spread out in the sun to dry. Then use a knife to cut the powder into thin slices and continue to dry them. The production of lotus root powder is now complete.

Of course, most of the lotus root powder we drink now is produced by modern machinery, with a higher degree of overall standardization, more stable quality, and higher output.

How does lotus root powder become a bowl of paste?

The main component of lotus root starch is starch, and starch gelatinization will occur when it is heated at a certain water content and temperature. Starch gelatinization goes through three stages:

The first stage: Starch is insoluble in water at room temperature even when soaked in cold water, but after stirring it will form an emulsion, also known as starch milk. If stirring is stopped, the starch particles will slowly sink again.

The second stage: under the conditions of the starch milk in the first stage, the starch is heated, and the starch will produce irreversible water absorption phenomenon. As the chemical bonds of the starch are broken, the amount of water absorbed by the starch increases rapidly, and the volume of the starch granules also expands sharply.

The third stage: As the starch granules absorb water and swell, when their volume expands to a certain limit, the starch molecules in the granules will expand outward, connect and entangle with each other, forming the paste we see.

After understanding the process of starch gelatinization, it is not difficult to understand the method of brewing lotus root powder: first add cold water that just covers the lotus root powder (about 1-2 spoons) and stir evenly, then add hot water above 95°C and stir quickly until the lotus root powder becomes transparent, and a bowl of delicious lotus root powder is ready.

The article is produced by Science Popularization China-Starry Sky Project (Creation and Cultivation). Please indicate the source when reprinting.

Author: Hydra Science Creator

Reviewer: Han Hongwei, researcher at the National Food Safety Risk Assessment Center