Carl Linnaeus, The Lapland Journey, translated by Peter Graves (Edinburgh: Lockharton Press, 1995), p. 113.

Jokkmokk, 05/07/1732, ¶576:

Reindeer milk gives twice as much cheese as any other milk, if not more. Butter is rarely made and, when they do make it, they do not use the cream as it does not set well. They use the milk itself, whisked in a bowl. It goes white.