The color of laver is influenced by the relationship between environment and growth period. Laver is divided into first water (water), two water, three water. One water (that is, the first time) harvest of laver, young and soft, with the increase of the number of harvest, laver gradually aging, its color, luster and taste are gradually worse. Altar laver and porphyra as the main economic algae in China, the application is different, altar laver is mainly dried into dry laver, used for cooking soup, and porphyra is mainly used to make nori, therefore, nori is laver, but not all laver is nori.
Nori is a thin sheet of striped laver, laver is round cake shaped laver; Nori processing is more complex. Laver as raw material needs to be cut, dried, baked and other steps, laver only needs to be dried to make; Nori can be eaten directly, nori needs to be cooked to eat; Nori is rich in iodine and selenium, and nori is rich in protein and dietary fiber. Nori is mainly used as a raw material in the production of snacks, such as crispy yaki nori snack,omelet,rice crackers,seaweed puff pastry,roasted seaweed roll,seaweed sandwich,traditional seasoned seaweed, while nori is mainly used as a food ingredient.