How to soak dried kelp bought in the supermarket in the most time-saving way?

There is no way to save time by soaking dried kelp. After soaking dried kelp in water for 5- 10 hour, its arsenic content is still as high as 5 mg/kg. After soaking in water for 24 hours, its arsenic content can reach the food safety standard. Therefore, the soaking time should be longer and the water should be changed frequently. This time can't be saved.

Kelp Kelp originated in Northeast Asia, including the Pacific coast of Russia, the northern coast of Japan and Korea, and grew up in Liaodong Peninsula and the coastal waters of Shandong in China. Today, China is the largest kelp producer in the world. Kelp spores are divided into three parts: fixator, stalk and belt. The growth period in natural environment is two years, and the breeding period in planting environment is two years.

Morphological kelp leaves are broad, and the tip gradually narrows, generally 2 ~ 5 meters long and 20 ~ 30 cm wide (kelp growing on the seabed is small, with a length of 1 ~ 2 meters and a width of 15 ~ 20 cm). The edge of the blade is thin and soft, with wavy folds, and the base of the blade is a short columnar petiole connected with the fixer. Kelp is olive brown. After drying, it becomes dark brown and dark brown, and white powder is sprinkled on it.