Because people in many European countries still like eating canned herring very much, canned herring can always exist as food.

canned herring is a national treasure food in Sweden, a Nordic country. The technique of making canned herring has been passed down for more than 3 years, and it has become an indispensable food in Swedish life.

In order to save salt, early Swedes adopted a method of preserving herring with little salt and fermentation: herring was smeared with a little salt, fermented for 2 hours to remove blood, canned directly without sterilization, and fermented in light salt water at room temperature for 1 to 2 months.

during the fermentation of herring, the anaerobic bacteria, monooxybromomethane, will participate in decomposing the meat quality of herring and convert it into oligopeptides and amino acids, which will make people feel delicious, but at the same time, it will also produce many odorous gases such as acetic acid, propionic acid and hydrogen sulfide, and produce various irritating smells.

Extended information:

Even in the place of origin of canned herring, the local people have been baptized by bad smell for a long time, and they still need to eat canned herring with their noses clamped. Japan once rated many stinky foods in the world, among which the stinky tofu in China was 42Au, the Japanese natto was 452Au, and the canned herring was 87Au.

Different from other canned herring, the microorganisms in the canned herring are still active when they leave the factory, and the anaerobic bacteria hydrogen bromomethane monooxygenase in the canned herring still participate in the decomposition, so many people buy canned herring which will swell, which makes them the highest-grade contraband, and it is forbidden to take them on the plane.

Baidu encyclopedia-canned herring (a kind of food)