E422: Glycerol (Glycerin Humectant & Solvent)

Direct Answer

E422 (Glycerol / Glycerin) is a sweet, viscous trihydroxy alcohol (polyol) obtained via lipid hydrolysis. INS 422, ADI is Not Limited (Quantum Satis), acting as an essential humectant, moisture retainer, and freeze-point depressant in baked goods and icings.

Source: Codex Alimentarius / EFSA · Last reviewed Aug 28, 2026

Specs

E-Number Code	E422
INS / Codex Number	INS 422
Functional Class	Humectant, Solvent, Sweetener, Bodying Agent
Acceptable Daily Intake (ADI)	Not Limited (Quantum Satis)
Chemical Formula	C3H8O3 (Propane-1,2,3-triol)
Primary Mechanism	Strongly hygroscopic triol binds water molecules, lowering water activity (aw) and preventing staling
Common Target Foods	Fondant icings, soft-baked cookies, energy bars, cake sponges, liqueur bodying
Dietary Compliance	Vegan (When derived from plant fats), Halal, Kosher
Safety Approval	EFSA Authorized / FDA GRAS (21 CFR 184.1320)

Anti-Staling Moisture Lock in Baked Goods

Adding 1–2% glycerol binds water tightly within starch-protein matrixes, keeping high-protein fitness bars and sponge cakes soft and pliable over months of storage without crumb hardening.