Stinkheads fermented whitefish

Freshwater whitefish

The freshwater whitefish are fish of the subfamily Coregoninae in the salmon family Salmonidae. Along with the freshwater whitefish, the Salmonidae includes the freshwater and anadromous trout and salmon species as well as graylings...

 heads, are a traditional food of the Yup'ik peoples in southwest Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

. A customary way of preparing them was to place fish heads and guts in a wooden barrel, cover it with burlap, and bury it in the ground for about a week. For a short while in modern times, plastic bags and buckets replaced the barrel, however this increased the risk of botulism

Botulism

Botulism also known as botulinus intoxication is a rare but serious paralytic illness caused by botulinum toxin which is metabolic waste produced under anaerobic conditions by the bacterium Clostridium botulinum, and affecting a wide range of mammals, birds and fish...

. Presently, Yupik Eskimo

Eskimo

Eskimos or Inuit–Yupik peoples are indigenous peoples who have traditionally inhabited the circumpolar region from eastern Siberia , across Alaska , Canada, and Greenland....

s typically ferment fishheads directly in the ground rather than in plastic to avoid the risk of botulism associated with the fermentation of animal products in plastic containers.