how is it treated to make it suitable for culinary purposes?
By parboiling it.
Amanita muscaria
Parboiling "A. muscaria" can detoxify them and render an edible fruit body. Although its consumption as a food has never been widespread, the consumption of detoxified "A. muscaria" has been practiced in some parts of Europe (notably by Russian settlers in Siberia) since at least the 19th century, and likely earlier. The German physician and naturalist Georg Heinrich von Langsdorff wrote the earliest published account on how to detoxify this mushroom in 1823. In the late 19th century, the French physician Félix Archimède Pouchet was a populariser and advocate of "A. muscaria" consumption, comparing it to manioc, an important food source in tropical South America that must be detoxified before consumption.

Use of this mushroom as a food source also seems to have existed in North America. A classic description of this use of "A. muscaria" by an African-American mushroom seller in Washington, D.C., in the late 19th century is described by American botanist Frederick Vernon Coville. In th
what is the red mushroom with white dots Amanita muscaria how did it get its name? The name in many European languages is thought to derive from its use as an insecticide when sprinkled in milk. Its scientific name was, however, given by Linnaeus and Lamarck. is it considered to be poisonous? Yes, it can be poisonous if ingested.
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Amanita muscaria [SEP] Culinary use
The toxins in "A. muscaria" are water-soluble. Parboiling "A. muscaria" can detoxify them and render an edible fruit body. Although its consumption as a food has never been widespread, the consumption of detoxified "A. muscaria" has been practiced in some parts of Europe (notably by Russian settlers in Siberia) since at least the 19th century, and likely earlier. The German physician and naturalist Georg Heinrich von Langsdorff wrote the earliest published account on how to detoxify this mushroom in 1823. In the late 19th century, the French physician Félix Archimède Pouchet was a populariser and advocate of "A. muscaria" consumption, comparing it to manioc, an important food source in tropical South America that must be detoxified before consumption.