Fish – Can gravlax be prepared from frozen salmon

You want to minimize the amount of fat you consume from farm-raised salmon. This means you should trim the fat from farm-raised salmon and avoid frying. Farm-raised salmon should be grilled, broiled, or baked, anything that burns away some of the fat. (Farm raised salmon is 52% fattier than wild caught salmon).

Why? Farm raised salmon have ridiculously high amounts of carcinogens known as polychlorinated biphenyls (PCBs) as compared to wild salmon, and many other foods for that matter. You can blame the feed they are given. These carcinogens are concentrated in the fat of the fish, which is why you want to minimize the fat intake. The levels of PCBs in farm-raised salmon can be 10 to 16 times higher than wild caught salmon, and up to 40 times the level found in other foods.

Experts recommend eating farm-raised salmon no more than once a month to minimize exposure.

Sources:

• http://www.ewg.org/reports/farmedpcbs
• http://www.healthcastle.com/wildsalmon-farmraisedsalmon.shtml
• http://www.seattlepi.com/national/132952_fish30.html

Alaskan King, or Chinook, salmon is generally wild, generally caught in the Pacific Northwest, often but not exclusively in Alaska. Scottish salmon is generally farm-raised Atlantic salmon, and as far as that goes is essentially identical to farm-raised salmon from Chile or Norway.

Price: hobodave's comment is correct that the price will vary based on location, but in fact the king salmon will be more expensive almost everywhere. Generic farmed Scottish salmon is a commodity product that generally sells for about $1 more than other farmed salmon for no particularly good reason, but wild salmon can easily cost twice as much regardless. Short of actually being in the Pacific Northwest it's likely that the Scottish is substantially cheaper.

Taste: the quality comparison is the big one here rather than species. King is usually treated much better (shipped quicker, wild diet) because it's not a commodity, but not necessarily. Scottish will vary depending on the farmer, but I think you have to prefer the King to any generically-farmed Scottish salmon.

Cooking methods: no necessary difference. Smoked on a plank is a common method in the Pacific Northwest, but no real reason you couldn't do either in that way. Pick your favorite method.