1, kelp into the pressure cooker, add a little water.

2. Press for 3 minutes.

3. Take it out of the pressure cooker, put it in water, soak it for more than 3 hours, and change the water halfway.

4, soaked, and then clean the impurities above, cut into silk or strips.

When choosing dried kelp, first look at whether there is white powder on its surface, because kelp is the food with the highest iodine content, and it also contains a valuable nutritional medicine-mannitol. Iodine and mannitol, especially mannitol, are attached to the surface of kelp in the form of white powder. Don't treat this powder as moldy inferior kelp, but kelp without any white powder is of poor quality.

Kelp is not easy to cook. When cooking kelp, you can add a little alkali and baking soda. During the cooking process, you can try the hardness and softness of kelp by pinching, and cease fire immediately after cooking. Pay attention to not adding too much alkali, and it should not be too long when cooking. Adding a few drops of vinegar when cooking kelp can make kelp soft and delicious quickly, and it is beneficial to the absorption of iodine by human body.

There is a layer of hoarfrost on the surface of dried kelp, which is a substance called mannitol formed by the weathering of plant alkali. It is not only harmless, but also has the function of detoxification and swelling reduction. Don't mistake that layer of hoarfrost for salt precipitation or moldy deterioration. There is a layer of mucus on the surface of kelp, so it is not necessary to wash it too much. In that case, many nutrients are lost.