I have bought what looks to be a defrosted raw salmon product in airtight packaging:
On the back of the package, it is written that this product can be stored in the fridge for up to a month from the day it was thawed, which is given.
Usually, this is not possible. For example, according to this great answer, raw proteins, specifically fish, can be stored in the fridge for 1–2 days.
I was unable to find more information on what makes this possible. I would like to learn what could make it possible to store uncooked fish in the fridge for up to a month.
I tried searching the internet, but I could not find any information regarding this, including in the Food Safety FAQ here.