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Alaskan aged fish heads ('stinkheads') and aged marine-mammal flipperstinkheads
Stinkheads are salmon heads aged in a pit in the ground until soft, an Alaska Native food; sea-mammal foods such as seal and whale are aged in a similar way. The state health guide calls this putrefaction rather than true fermentation, since no carbohydrate is there to make acid and the pH stays neutral. Aging was the preservation method in 85 of Alaska's 141 foodborne botulism outbreaks from 1950 to 2010; type E caused 83 % of all the outbreaks.
A short entry: the sources we found record only what is said here about Alaskan aged fish heads itself.
Short entryFish and seafood
Recipe
No fixed amounts recordedNo fixed amounts; heads are aged in whatever quantity is caught.
What changes:Starting material: heads of salmon caught in summer
Step 1 of 4
Take the salmon heads
Time
Not documented
Temperature
Not documented
Salt
None given
Acidity
Not documented
In the account Nelson gave of 1877–1881, the heads were from king salmon taken in summer.
Flavour
Not documented
Texture
Not documented
Colour
Not documented
Microbes at work in this step
Not documented for this step.
Method
Measured measured in a studySet fixed by a specification or tested recipeReported one source reports itTypical a general value, not sourced for this fermentUnconfirmed not yet checked against a source
At a glance
Stinkheads are salmon heads aged in a pit in the ground until soft, an Alaska Native food; sea-mammal foods such as seal and whale are aged in a similar way. The state health guide calls this putrefaction rather than true fermentation, since no carbohydrate is there to make acid and the pH stays neutral. Aging was the preservation method in 85 of Alaska's 141 foodborne botulism outbreaks from 1950 to 2010; type E caused 83 % of all the outbreaks. No true fermenters; the guide describes the aging as putrefaction, the breakdown of protein and fat does most of the fermenting.
Unlike most fermented fish, stinkheads have no carbohydrate to turn into acid, so the pH stays near neutral. Nothing in the method itself holds back C. botulinum, which is why sealed modern containers raise the risk.
Alaska had 141 confirmed foodborne botulism outbreaks, 283 cases and 20 deaths from 1950 to 2010, all from traditional Alaska Native foods; 14 outbreaks were traced to salmon heads. Type E strains, which are inhibited only below pH 5, caused 83 % of the outbreaks. Plastic or glass jars and sealed plastic bags keep air out and raise the risk. In a survey of 140 adults in nine Bristol Bay villages, one third of those who made these foods used plastic containers. The state advises traditional methods, aging cold (ideally below 2 °C), clean hands and containers, and cooking the food before eating, since heat destroys the toxin. The guide says traditional methods may decrease botulism bacteria but will not always prevent toxin production. Outbreak foods were aged in pits as well as in closed containers. CDC advises boiling all home-fermented Alaska Native foods for 10 minutes before eating, with 1 more minute for each additional 1,000 feet of elevation. You cannot see, smell or taste the toxin, and even a small taste can be deadly.
Hazards the sources name: Clostridium botulinum type E (83 % of Alaska's confirmed outbreaks, 1950–2010); Clostridium botulinum types A and B (fewer cases).
Nelson described king salmon heads aged in straw-lined pits in the villages between the Yukon and Kuskokwim in 1877–1881. In a 1987 Bristol Bay study, only 13 % of preparers still aged fish heads the traditional way in a clay pit; 42 % used a wooden barrel above ground.