Shredded kelp can be cooked for 1-2 minutes. Kelp, also known as spandex, kombu, jiangbai, is a perennial large edible algae, its leaves for the epidermis, cortex and medulla tissues are composed of, the leaves are wide and thick, the lower part of the sporocarp, with a mucus cavity, can be secreted slippery substances, compared to other vegetables, its cooking time is relatively longer some, generally the large sea kelp after the hair of the sea after the water slices need to be cooked in the water boiled for 5 minutes in order to be cooked, and cut thin kelp shreds, only need to blanch for 1 minutes or so to cook.

The kelp contains fucoidan, alginate and other substances, once absorbed, it will make the surface of the kelp appeared viscous colloid, preventing water from further immersion, in addition to the nutrients in the kelp, such as water-soluble vitamins, minerals, etc. will also be dissolved in water, long-term immersion, the nutritive value will be reduced, it is recommended that the dry kelp, the seaweed on the steamer basket, dry steaming for half an hour, and then immersed in water for two to three hours, soaked in water, so that it is easier to cook soft. This way the kelp is easier to cook soft. Fucoidan, however, is easily soluble in alkali, put a little edible alkali or baking soda before steaming, so that the kelp gel is easily dissolved by alkaline substances, a cook quickly become soft and rotten.