Great source of dietary fiber and minerals including calcium, iron, and iodine.

For dried kombu, products that are well-dried, strongly aromatic and brown in color are of high quality. Be sure to store in a dry location avoiding dampness and humidity. The white powdery substance on the kombu surface is mannitol, a type of carbohydrate. Wipe this away with a well-wrung cloth prior to usage.

Makombu kelp and Rishiri kombu kelp are suitable for use in dashi broth. Hidaka kombu kelp (Mitsuishi kombu kelp) is suitable for use in both dashi broth and simmered dishes. For oden (wintertime hot-pot) dishes and kombu-maki (stuffed kelp rolls), Hayani kombu kelp, which can be quickly boiled is recommended. Oboro (Tororo) kombu kelp is kombu kelp soaked in vinegar to soften and then shaved into thin strips to make it suitable for soups and toppings. Knotted kombu kelp is bite-size, used in dishes such as Nishime (a simmered vegetarian plate) and is sold pre-knotted. Since sliced kombu kelp prepared fresh need not be rehydrated, it can be easily used in cooking, and is suitable for both simmered dishes and as a topping.