Tundra Medicine Dreams, a blog devoted to the challenges of bush medicine in Alaska, explains why you should ferment your fish heads the old fashioned way:
Stinkhead is made from the whole head
of a King salmon, which is somewhat larger than a football. The
traditional method of preparation was to wrap the fish head in the long
grasses which grow along rivers and streams, and then to bury it in a
moss-lined pit in the ground for four to six weeks. Where it rots. And
then dig it up and eat it. Yum. The bones soften up until the whole
head has a mashable consistency. The dish gets its name from the smell,
which is every bit as rancid as you might imagine. I can’t even be in
the same room with it, much less consider putting it in my mouth.
Another
fermented delicacy is “stinkeggs”. The female salmon have large roe
sacks when they are caught in the summer. These are buried intact along
with the heads; the surface dries out and becomes quite firm, leaving
the interior soft.
As aesthetically distasteful as these dishes
might seem, the health problem stems from the method of preparation,
not from the dishes themselves. As long as the fish head was wrapped in
grass before burial, it fermented aerobically and slowly at cool
temperatures buried just on top of the permafrost. But then someone
discovered that placing the fish head in a Ziplock bag, or plastic
bucket with a lid, speeded up the fermenting process significantly.
Stinkfood could be made in about half the time. Additionally, now the
food is sometimes left unburied, so it ferments at warmer temperatures.
The result of these changes is an increased incidence of botulism.