How long should dried seaweed be soaked for safety

Dried kelp generally needs to be soaked for 6-12 hours to be safe, and the specific time is affected by factors such as water temperature, kelp thickness, and consumption method. Dry kelp has a hard texture and contains a lot of sea salt and possible residual impurities. Adequate soaking can soften it and reduce salt content. Soaking in cold water requires a longer time, usually 8-12 hours, during which the water should be changed every 2-3 hours to accelerate desalination. If soaked in warm water, it can be shortened to 4-6 hours, but the water temperature should not exceed 40 degrees to avoid damaging the water-soluble vitamins in kelp. For thicker kelp or for cold mixed raw food, it is recommended to extend the soaking time to at least 12 hours to ensure complete rehydration. Some rapid processing methods such as high-pressure steaming and soaking for 2 hours can also achieve softening effect, but the taste may be slightly soft and rotten. It should be noted that commercially available dried seaweed may contain trace amounts of heavy metals such as arsenic, and prolonged soaking can effectively reduce the risk. If the kelp still feels hard or has a smooth surface after soaking, it may be a low-quality product and should be stopped from consumption. It is recommended to use glass or ceramic materials for soaking containers to avoid chemical reactions with metals.

After soaking seaweed, it is recommended to repeatedly scrub with running water to remove surface attachments. Before cooking, blanch for 1-2 minutes to further sterilize. Daily consumption should not exceed 3 times a week, and patients with thyroid diseases should consult a doctor. Pairing with ingredients such as tofu and radish can promote nutrient absorption and avoid consuming high tannic acid foods that can affect mineral utilization. When storing, it is necessary to drain the water and refrigerate, and consume as soon as possible to avoid the production of nitrite.