I make a lot of sushi. But, as I buy the paper/wrapper in 100's, sometimes I do not use it in what might be considered good time. I have searched and searched the packet for a sell or eat by date but there is none. Is this OK to use even though I bought it about 8 months ago, and opened it about 6 months ago. I have made sushi today from it, it seems OK, rolled great and cut brilliantly, but should I be concerned? The paper is not too dry on the edges and is still a great greeny/blackish color.
I just checked with my Chinese wife. She confirms that it doesn’t go bad but just is less tasty.
My instinct is that it's very dry, so it will last for years without going rancid or becoming inetable, if kept in a climate that's not super humid (or kept in the fridge which is very dry air).
According to Still Tasty (a site that looks at USDA, CDC and FDA data), nori lasts 2-4 months in the pantry and 4-6 months in the fridge. Also it says:
Store in airtight glass or plastic container or in sealed plastic bag. Refrigerate to extend shelf life.
Still, nori is completely dried. I imagine that the concern beyond that time frame is staleness, not safety.
I have nori that's years old. I would check to be sure that it is somewhat brittle, not leather-like before I used it, but for quality, not safety.
Once opened, unless tightly sealed in a not-too-big airtight container, it goes stale and leathery quite quickly. So although I would use it out of date (and probably have) it's likely to be past its best having been open so long.
It's not going to do you any harm if it's just lost some texture though - so try it and see.
I like my nori chewy, personally. You could store it in an airtight container with a packet of silica gel (electronics equipment usually comes with one or more inside the box- and they can be regenerated in the oven), and that would probably keep it from going off but it would dry out faster.