Buttermilk
Primary source
Verbatim text below is from the Electronic Code of Federal Regulations (eCFR), a public-domain U.S. government work. Always verify the current version with the eCFR before relying on it for any legal matter.
Full Text
Buttermilk for drying as dry buttermilk or dry buttermilk product shall be fresh and derived from the churning of butter, with or without the addition of harmless lactic culture. No preservative, neutralizing agent or other chemical may be added. Fluid buttermilk, unless cultured, shall be held at 45 °F or lower unless processed within 2 hours.
[56 FR 33855, July 24, 1991]
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