Glycerin (E422): Plant, Animal or Synthetic?

Glycerin is a source-ambiguous workhorse: chemically identical whether split from vegetable oil, split from animal tallow or made synthetically, and food or cosmetic labels rarely say which. Vegetable glycerin dominates food supply, but tallow-derived glycerin remains in circulation — especially in soaps and older cosmetic supply chains — so certified claims rest on the supplier's origin statement.