Glycerine USP — also known as glycerine or glycerol — is a clear, odourless, viscous liquid and the backbone of moisturising soap. Naturally produced during saponification, this powerful humectant draws moisture from the air into skin and hair. USP-grade ensures 99.7% purity — safe for food, pharma, and cosmetics. This Australian guide covers its science, benefits, and DIY uses.

What is Glycerine USP?

C₃H₈O₃ — a triol sugar alcohol derived from vegetable oils (palm, coconut, soy) or animal fats. USP = meets United States Pharmacopeia purity standards.

Key Properties

• Humectant: Attracts water (up to 20% of its weight)
• Emollient: Softens skin
• Hygroscopic: Pulls moisture from air
• Non-toxic, biodegradable

Glycerine in Soap Making

1. Natural Moisturiser

By-product of saponification — stays in soap (unlike commercial bars that remove it).

2. Gentle & Non-Irritating

Ideal for eczema, psoriasis, sensitive skin.

3. Transparent Bars

Allows embedded flowers, swirls, clear designs.

Glycerine in Skincare

• Hydration Boost: Draws water into stratum corneum
• Barrier Repair: Strengthens skin lipid layer
• Anti-Aging: Plumps fine lines
• Soothing: Calms redness, heals cracks

Glycerine in Hair Care

• Reduces Frizz: Seals cuticle
• Prevents Breakage: Adds elasticity
• Scalp Health: Balances moisture