The main producing areas of nori are China, Japan, and South Korea. Among them, China is a country that produces nori earlier, while Japan's overall nori production technology has developed and been applied earlier, and there is a great demand for nori. Japan's famous food -- sushi cannot live without yaki sushi nori. This also reduces the need to raise raw materials for nori.
In the early years, the cultivation of laver, which is the raw material of nori, has been changed from the traditional bamboo pillar cultivation in coastal intertidal fisheries to the deep-sea fisheries. Methods have also been developed to directly cultivate laver without drying laver nets. In some cases, the cultivation of laver can be carried out without reducing the area of fish farms. Some have also expanded farming and fishing grounds.
In the traditional pillar culture process, due to the difference in water level caused by the ebb and flow of seawater, laver mesh is exposed to the air, thus obstructing the growth of dialogue and weak buds of laver. This method of culture was once considered the most suitable way for laver cultivation. However, after the development and application of the cold storage technology of laver mesh, people found that when picking seedlings manually, The weak laver sprouts are separated by freezing to a certain extent, and in addition, seedlings are raised and farmed in high water temperatures by controlling the amount of sunlight. However, research has found that it is possible to breed in deep water where the high water temperature is not easy to control. Therefore, a method of growing seedlings by covering the sea area with fixed laver nets has been developed.
In China, Japan, South Korea, and other coastal countries producing nori, the technology of artificial nori breeding has been upgraded and improved, and great progress has been made in improving the yield and quality. China has not only increased the demand of domestic consumers but also exported a large amount of nori to the world to meet the demand for nori.