First cold smoked salmon

Hot smoking was definitely a smart choice rather than tossing. I'm just getting in to smoking salmon myself so not experienced enough to tell you anything definitively.

One thing I do know from my research on sushi to make it at home, is that where the salmon comes from is important regarding potential parasites. I haven't read anyone yet address this for smoking, the main focus seems to be on pathogens and curing them dead essentially, and handling the fish in a way that wont produce more or new pathogens. (again, this is just discussion because I am no expert on this).

Salmon can come from the ocean, river, somewhere in between and also farms. They typically run up in to rivers to spawn and die, then the young hang around for a while, get their system ready and head out to sea. Some salmon are fresh water trapped and have even been released and thrive in the great lakes.

From my research, ocean salmon are the ones that can be eaten raw. I suppose the young don't develop freshwater parasites or the parasites die when they become ocean fish. The thing is, parasites in ocean fish are large and you can see them when you cut in to the fish, where a fresh water fish parasite is microscopic.

This is why fresh ocean salmon can be eaten raw while fresh water salmon, and all fresh water fish must be cooked to be sure there are no parasites. So for me, if I'm going to cold smoke, I plan to use ocean salmon rather than salmon farm raised (unless its somehow certified as ocean farmed) or river identified salmon like "copper river" and such. Again I am no expert on salmon and welcome correction from anyone that is. I am just commenting and not suggesting you do what I do at this point.

But, there are concerns about bacteria that can cause spoilage. Gravlox is not even smoked per this recipe/method presented by Mario Batali:

http://www.mariobatali.com/curing-salmon/

He doesn't go in to sourcing the fish, which is my point. From what I have learned, you don't want to eat raw freshwater salmon and that method Mario shows does not cook or smoke at all, just cured with salt and sugar and put under pressure in the fridge for three days.

Sushi research can be as sketchy as trying to find consensus on brines, times, temps, etc. for smoking. One consistent thing you find is what might kill you or make you very sick..."might" not "will". With sushi, you will find that some will say ONLY very fresh fish must be used, but deep in the bowls of sushidom you can reveal that some of the best sushi chefs on the planet purposely freeze their fish to improve texture, much like you find here about the different characteristics of fresh and frozen salmon and how you should approach brining. The deeper little secret you will have a very hard time finding, is many sushi places bring all their fish in frozen. Yes, it was frozen fresh but may have been frozen for weeks before thawing and serving as sushi! It is still safe to eat, as is fresh caught delivered next day ocean salmon fillets. There is no fear of bacteria, you just slice it thin and eat it. Bacteria is what can develop if it is allowed to sit for a length of time and I assume that's the big fear with bacteria in cold smoked salmon.

I equate this to sushi because the big fear is getting sick. A lot of people are freaked out eating raw fish, but the reality is that the source of the fish and the freshness, even before it may have been frozen, matters, and the freezing of commercial fish is done in a deep freeze, not a home freezer...it makes a difference with bacteria. What I don't know is if the brining procedures we see for smoking salmon kills parasites as well as bacteria. That's why I say for myself, when I move to cold smoking, I am going to start with fresh ocean fish that is sushi safe (basically fresh or freshly deep frozen). Everything else I will hot smoke to safe temps until I know more.