Many Asian foods call for the use of nori, a type of edible seaweed which is dried or toasted, and often sold in sheets. Nori has been consumed in Japan and China for centuries, and is an important part of Japanese cuisine especially. Most Western consumers are familiar with nori because it is used to wrap sushi, although the distinctive salty, slightly grassy flavor is also delicious eaten plain as well.

Nori comes from the genus Porphyra, which contains a variety of species that are commercially grown and harvested to make nori, including Porphyra yezoensis and Porphyra tenera. The sea dwelling algae are grown in enclosed nets, which can be easily pulled out of the water for harvesting. In color, the genus ranges from red to green, and grows in wavy fronds which can be found growing naturally on rocks and attached to other seaweeds such as kelp.

Once the seaweed is harvested, it is washed and shredded before being pressed into molds to dry, forming paper like sheets of seaweed. Nori is often sold plain just like this for use in a variety of foods including soups. However, nori can also be toasted and flavored for use in other dishes or for consumption as a snack food. Toasted nori flavored with soy sauce and dipped in sesame seeds, for example, is a popular treat in Japan.

Nori comes in a wide range of colors and flavors, depending on what type of seaweed was used and how it was treated. Some nori can be reddish to brown in color, while dark green nori is familiar to many consumers. In addition, nori which is dark purple or almost black can be obtained, and is very popular for making sushi because the dark color contrasts beautifully with the sushi rice used.

In addition to being used in soups and sushi, nori is also shredded and scattered on rice dishes and stir fries. Finely shredded nori often appears as a condiment, thanks to the salty flavor and crunchy texture. Some consumers also greatly enjoy eating whole sheets of sushi nori dipped in soy sauce. Some Chinese cooks use nori or other seaweeds as well, especially in traditional soups featuring fish and other sea vegetables.

Because of its popularity for sushi, toasted nori is readily available in most markets around the world. Specialty stores may also carry special nori snack foods, along with untoasted nori and other dried seaweeds. When using nori to cook, make sure to handle it carefully, and do not allow it to get wet, because it will grow soggy and rubbery. If you do not use up an entire package, seal it well so that it will not get moist or stale.