Round 1: grilled
It’s probably from the yeast extract which is part of the heme
To be clear tho it still doesn’t have all that much salt. It’s more that raw beef just barely has any. Both impossible meat and raw beef pale in comparison to the salt content of the final burger, where the sodium content skyrockets from things like ketchup, pickles, seasoning the patty during cooking, the salt content of the bun, etc
And imo you should still salt/pepper an impossible patty after formation. As mentioned, while the salt content is higher, it’s still not terribly high, and imo it benefits from a bit more. In my experience it’s not like meat and you can salt whenever you want (whereas with beef you generally want to salt patties absolutely last minute to avoid giving the meat a lightly cured texture)
