Ok, here is the most direct answer I've found so far: No. IF you cure it, you don't need to freeze it.
See Below
From: https://happyspicyhour.com/do-you-need-to-freeze-salmon-before-making-sushi/
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Hey foodies! If you’re a sushi lover like me, you may have wondered – do I really need to freeze salmon before making sushi? I totally get it. Who wants to wait around for fish to freeze when fresh sushi-grade salmon is waiting for you at the store? But before you whip up a homemade sushi roll, there are some important safety steps to take.
Let me walk you through the scoop. Freezing salmon for at least 7 days kills any nasty parasites that could make you sick. I know, not fun to think about. But curing salmon in a salty mixture works too! Once frozen or cured, the salmon is safe to eat raw in sushi and tastes delicious.
Now, you can sometimes get away with using a fresh fillet from a reputable fishmonger or local sushi joint. But to be on the safe side, I recommend freezing or curing that salmon first. Trust me, it’s worth the wait to avoid biting into something extra squiggly.
Alright, now that we’ve got the safety stuff out of the way, let’s talk about how freezing and curing makes for mouthwatering sushi! Stick with me as we dive into the secrets behind tantalizingly tender sushi salmon. There’s a whole world of flavor waiting for us!
Freezing Salmon Kills Parasites and Bacteria
Raw salmon can sometimes contain nasty little critters like worms and parasites. Freezing fish for an extended time kills them off, along with dangerous bacteria.
According to the FDA, salmon should be frozen at -4°F (-20°C) or below for at least 7 days to eliminate parasites. Extending the freezing time to a full month provides an extra safety buffer.
So if you plan to eat that beautiful salmon fillet raw in sushi, first freeze it for optimal safety. It gives you peace of mind knowing there’s nothing wiggly inside!
Curing Also Works to Prepare Safe Sushi Salmon
Now, you don’t necessarily have to freeze salmon to enjoy it raw if you cure it instead.
Popular curing methods involve covering salmon fillets with salt, sugar, spices, and herbs for several hours. This process draws moisture out of the fish while infusing tons of flavor.
The salt also kills any lurking parasites and bacteria. So curing makes for safe and tasty sushi salmon too.