As I try recipes from far off lands and constantly look for new ways of eating a Trout, I sometimes have to fall back on old, and I mean OLD classics. Evidence of fish smoking dates back thousands of years and was used by various groups of people to preserve their catch. With cold smoking in the Norse method, you basically do several things to preserve and flavor the fish, which is, in essence, raw. I've just made a Lox like product from some large Rainbow Trout, and I can say with certainty that is one of the best things I've ever put in my mouth. Let's go over the process, it's easier than you think!
For me, using a freshwater fish for a raw product just sounds scary. Although the high waters where we catch these fish are relatively clean on the global scale, there are still parasites and bacteria present that could pose a health risk, which is why we have to be meticulous about our preparation and not cut any corners. Done correctly, this fish is as safe as anything you can buy. The FDA states that freezing at a temperature of -4F for a period of 7 days will kill unwanted parasites such as tapeworms. A physical inspection is also handy for tapeworms, and they're often large enough to see with the naked eye. You can also freeze at -31F for 15 hours, but you better have a beefy freezer for that. Check your freezer's temperature, many home models do not go below 0, and this temperature will not kill parasites. I got lucky with a freezer that holds around -10F and I stored my fish in it for 8 days just to be safe.
While the freezing takes care of parasites, we do have bacteria to worry about. Cleanliness and promptness are required when filleting the fish for the smoker. Be very careful with the kidney, along the spine of the fish. We don't want any of that nastiness getting on our fillets. Once the fillets are removed, they need to be cleaned, dried, and frozen immediately. Again, watch that freezer temperature. If you don't have a freezer that can reach these temperatures, reach out to your friends in the food service industry. Many restaurants have a deep freezer.
Once the fish have been adequately frozen and have thawed, we want to coat them, and I mean COAT them with a mixture of salt and brown sugar. I do about 2/3 salt and 1/3 brown sugar. We want the fish to be entirely caked, get the nooks and crannies. This is no time to be stingy with your salt, go big or go home. Once salted, wrap the individual fillets in clingwrap and place in dishes that can catch spillover, in the refrigerator. Some people say 6 hours, but I found that leaving them over night gave the fish time it needs to shed water. You'll notice that your fish has dramatically reduced in size, and should be surrounded by liquid. Rinse off excess salt and sugar and place the fish on racks to dry. They'll feel more firm and they'll be smaller and lighter. This curing process removes water from the meat and adds salt, creating a hostile environment for bacteria. The bacteria need the water in the meat to reproduce and flourish, and we've just taken the water away. Your fish is now cured, and could be eaten, but why leave out the best part?!? These fish are cured and ready to smoke.
Hot smoking cooks the fish, while cold smoking really just adds flavor. You can build your own cold smoker, I used an old BBQ with a fire in it connected with some duct to a platform. I placed my fish on racks on the platform and covered with a giant tupperware. It looked like something from Sanford and Sons' yardsale, but it did the trick just perfectly. I used hickory to get the fire going and then apple wood once the fish was actually in there. You'll want to keep the temperature under 80F, remember we're not trying to cook the fish. Smoke from 6 to 12 hours, depending on how smoky you like it. Don't be afraid to try a bit as it goes, it's the best way to monitor the flavor.
What I ended up with was an insanely delicious product served on crackers with cream cheese, or just eaten as slices right off the fillet. I can't believe it's taken me this long to produce a product like this. Sure, there's an element of risk, like there is in anything worth doing, but the payoff makes it all worth it!