This article is from the Food Preserving FAQ, by Eric Decker ericnospam@getcomputing.com with numerous contributions by others.
from Doug Smart, ...
This isn't a recipe, but it is good information and does offer something on
the strength of the brine:
Pacific Northwest Cooperative Extension publication PNW 238 advises the fol-
lowing (somewhat paraphrased) for safety in smoking fish:
- Fish must be heated to 160 F internal temp and held there for at least
30 minutes during the smoking process.
- Fish must be brined long enough to absorb adequate salt for preservation.
A brine solution containing 1 part salt to 7 parts water by volume for 1
hour will usually suffice.
- Oily fish such as salmon, steelhead, shad, and smelt take longer to absorb
brine, but tend to absorb smoke faster.
- Fish should be air dried before smoking for better smoke absorption and to
minimize the chance of spoiling during smoking.
- It is best to smoke at a low temp for 3-5 hours before elevating to the
160 F cooking temp. This helps eliminate "curd" formation as juices boil
out. To avoid spoilage during smoking, the magic 160 F temp should be
reached within 6-8 hours.
- Commercial smoked products must meet an FDA requirement of at least 3 1/2%
water phase salt after smoking. Since most home smokers cannot make that
measurement, refrigeration is essential for safe storage of home-smoked
fish.
- Use only hardwoods for smoking. Maple, oak, alder, hickory, birch and
fruit woods are recommended. DO NOT USE WOODS FROM CONIFERS.
 
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