Nori: Toasted and Untoasted Sushi Seaweed, and Which Side Faces Out

What is nori?

Nori, in Japanese 海苔, comes from red algae of the genus Pyropia, formerly called Porphyra. Japan, Korea and China grow the algae on nets in shallow coastal waters. After harvest, producers chop the algae fine, spread the slurry thinly on frames and dry it much as in papermaking. The standard sheet measures about 21 by 19 cm.

Nori tastes of the sea, slightly salty and toasty, with clear umami. Good sheets are an even dark green to black, shine on one side and have hardly any holes.

Types: toasted, untoasted, seasoned

• Yaki nori (焼き海苔): toasted, green-black, crisp. These sheets are sold in the supermarket as “sushi nori”. You use them straight away.
• Hoshi nori (干し海苔) or untoasted nori: purple to brown-black and less aromatic. You toast them yourself before use.
• Ajitsuke nori (味付け海苔): brushed with soy sauce, sugar and spices and cut into small strips. In Japan they lie next to the rice at breakfast.
• Korean gim (김): thinner, toasted with sesame oil and salt. Ideal as a snack, too oily and too brittle for sushi. For Gimbap there are separate, unseasoned gim sheets.
• Kizami nori: sheets cut into fine strips as a topping for noodles and rice bowls.

You toast untoasted nori like this: hold the sheet with tongs 10 to 20 cm (4 to 8 in) above a gas flame or a hot stovetop and move it back and forth for a few seconds until it turns green and smells fragrant. Two sheets toasted with the rough sides together toast more evenly.

Which side faces out?

Each sheet has a smooth, shiny side and a rough, matte one. For the classic Maki roll you lay the sheet shiny side down on the bamboo mat and spread the rice on the rough side. The rice sticks better there, and on the outside you see the nice side. For the Inside-out roll the rice is on the outside, so the seaweed side hardly matters.

Handle nori with dry hands. Wet fingers make the sheet soft and sticky at once. To cut finished rolls, use a sharp knife that you wipe with a damp cloth before every cut. That way you don't crush the roll, and the seaweed tears cleanly.

The sheets also have fine lines running in one direction. Roll parallel to these lines, and the sheet tears less often. For thin hosomaki, halve the sheet along the lines.

Uses in the kitchen

• Sushi: Maki, uramaki and Temaki. The basis is well-seasoned Sushi rice with rice vinegar.
• Onigiri: With Onigiri you wrap the strip around the rice ball only shortly before eating, or it turns soft.
• Ramen: Half a sheet is tucked in at the edge of the bowl, as in the Shio ramen with mushrooms and nori. It soaks up broth and brings a sea aroma.
• Seasoning: Crumbled nori belongs in Furikake, on rice with egg or in dressings.

Don't mix them up: aonori is a green seaweed powder from other algae, sprinkled over okonomiyaki and takoyaki. It doesn't work as a substitute for nori sheets, but it does as a sprinkle seasoning.

Iodine and allergens

Like all seaweeds, nori contains iodine, though far less than kombu. Check the information on the package. Seasoned types often contain soy sauce, wheat and sesame; plain yaki nori contains only seaweed.

Buying and storing

You find toasted nori in packs of 10 or 50 sheets in the Asian aisle of most supermarkets, at an Asian grocery store and online. Large packs at an Asian grocery store cost less per sheet. Seasoned Korean snack nori usually sit on the snack shelf there.

Moisture is the enemy of nori. Close opened sheets airtight right away, best with the included desiccant packet. This way they keep for a few weeks. For longer storage, the well-sealed bag goes in the freezer. Sheets that have turned chewy you toast briefly over the flame, and they turn crisp again.