GMS (Glycerol Monostearate) Powder

✦ Versatile cosmetic emulsifier and co-emulsifier that stabilizes oil-in-water and water-in-oil systems across creams, lotions, and hair care products.
✦ Functions simultaneously as a viscosity builder and thickener, imparting a rich, smooth body to emulsion formulations without relying solely on thickening polymers.
✦ Delivers a velvety, non-greasy skin feel and improves the emollient spreadability of oil-rich formulas across all skin types.
✦ Provides natural opacification and a pearled, premium appearance to white cosmetic emulsions without synthetic opacifiers.
✦ Derived from vegetable-source glycerol and stearic acid — vegan-compatible when sourced from non-animal origin and biodegradable under standard conditions.
✦ Broad application range covering body lotions, cold creams, body butters, hair conditioners, face creams, and scrub bases.
✦ Heat-stable during hot-process emulsification and compatible with a wide range of emulsifiers, waxes, thickeners, and active ingredients.

Glycerol Monostearate, commonly abbreviated GMS and sold in its powdered form under the INCI name Glyceryl Stearate, is a mono-ester derived from the partial esterification of glycerol with stearic acid. Stearic acid is typically sourced from vegetable fats such as palm stearin or sunflower oil, making plant-derived GMS a widely accepted vegan cosmetic ingredient. GMS has been used in food, pharmaceutical, and cosmetic manufacturing since the early twentieth century and remains a benchmark emulsifying wax component in classical and modern cosmetic formulation systems globally.

The cosmetic utility of GMS rests on its amphiphilic molecular structure, which contains both a hydrophilic glycerol head and a lipophilic stearate tail. This structure allows it to position itself at the oil-water interface and reduce interfacial tension, stabilizing emulsions against separation. In practice, GMS functions most effectively as a co-emulsifier and texture agent when combined with a complementary hydrophilic emulsifier such as polysorbate 60, ceteareth-20, or stearic acid and an alkali-based soap system. Its HLB value of approximately 3.8 means it contributes to the overall emulsion HLB balance rather than acting as a complete standalone emulsifier in most oil-in-water systems.

Rabibazaar supplies cosmetic-grade GMS Powder suitable for DIY beauty formulators, skincare and body care product developers, salon and spa brands, and professional cosmetic manufacturers across Pakistan.

INCI Name : Glyceryl Stearate
Chemical Name : Glycerol Monostearate; 1-Stearoyl-rac-glycerol
CAS Number : 31566-31-1
Molecular Formula : C21H42O4
Appearance : White to off-white fine powder, flakes, or beads
Odor : Faint fatty or waxy odor
pH (1% solution) : 6.5 – 7.5 (in warm aqueous dispersion)
Solubility : Insoluble in cold water; dispersible in hot water above 60°C; soluble in hot oils, ethanol, and acetone
Specific Gravity : 0.97 – 1.02
Flash Point : Above 200°C
HLB Value : 3.8 (standard grade); approximately 5.5 (self-emulsifying SE grade)
Recommended Use Level : Co-emulsifier in O/W emulsions: 1–5%; Thickener and texture agent: 2–8%; Body butters and balms: up to 10%
Type : Vegetable-derived non-ionic emulsifier and co-emulsifier
Shelf Life : 2 years when stored sealed, away from heat and moisture

Skincare (Creams, Serums, Lotions) ★★★★★
GMS is a primary structural component of classic cream and lotion formulations, contributing emulsion stability, viscosity, and a smooth skin feel. Use at 2–5% in the oil phase of O/W emulsions alongside a hydrophilic co-emulsifier for best results.

Haircare (Conditioners, Hair Masks, Leave-in Creams) ★★★★☆
GMS provides excellent slip, detangling lubricity, and a conditioning coating effect in rinse-off conditioners and hair masks. Use at 1–3% in the oil phase alongside cetyl alcohol and BTMS or conditioning emulsifiers for a creamy, spreadable texture.

Soap Making (Cold Process, Melt and Pour) ★★☆☆☆
GMS has limited function in cold process saponification and does not contribute meaningfully to bar soap performance at standard inclusion levels. It can be used as a skin-feel additive in melt-and-pour bases at 1–2%, but soap making is not its primary application category.

Body Care (Butters, Balms, Body Lotions) ★★★★★
GMS is an outstanding body butter and balm structuring agent, adding a smooth, non-sticky texture and improving emollient spreadability across skin. Use at 3–8% alongside shea butter, cocoa butter, and carrier oils for rich-bodied, well-structured body care products.

Functional Cosmetics (Sunscreen, Baby Care, Mineral Formulas) ★★★★☆
GMS is suitable in mineral sunscreen formulations and baby care creams where a simple, mild, well-tolerated emulsifier system is required. Its clean regulatory profile and mild skin interaction make it particularly appropriate for sensitive or infant skin formulations when used at 2–4%.

In my formulation work, GMS is the first ingredient I reach for when I need both emulsification support and a specific texture character simultaneously. I do not treat it as a simple emulsifier — I treat it as a texture architect. The amount of GMS I use directly determines whether the finished emulsion feels light and fast-absorbing or rich and lingering on the skin, and I adjust that percentage based on the intended consumer experience of the product.

ADVANCED TIP: To build a stable, globally compliant O/W body lotion without synthetic polymer thickeners, combine GMS at 3% with cetyl alcohol at 2% and stearic acid at 1% in the oil phase, then use polysorbate 60 at 1.5% as the hydrophilic counterpart. This classical four-component emulsification system produces a white, opaque lotion with excellent freeze-thaw stability, a pH-stable structure between 5.0 and 7.5, and a smooth, non-sticky after-feel. Melt the oil phase together at 75–80°C, heat the water phase to the same temperature, and add the water phase to the oil phase with continuous stirring before cooling with slow agitation to 40°C prior to adding heat-sensitive actives.

Normal Skin : ★★★★★ — Performs excellently in a wide range of formulation weights from light daily lotions to richer overnight creams.
Dry Skin : ★★★★★ — The emollient-locking and skin-conditioning character of GMS in rich emulsion systems is particularly beneficial for dry, dehydrated skin.
Oily Skin : ★★★☆☆ — Suitable in lightweight lotion formats at lower inclusion levels but heavier GMS-based creams may feel occlusive and uncomfortable on oily skin.
Combination : ★★★★☆ — Works well in balanced O/W lotion formulas for combination skin when the total oil phase is kept lean and lightweight carrier oils are selected.
Sensitive Skin : ★★★★☆ — GMS is well-tolerated on sensitive skin and carries a low irritancy profile, making it a preferred emulsifier for reactive and fragrance-free formulations.
Mature Skin : ★★★★★ — Rich GMS-based creams and butters support the lipid barrier reinforcement and emollient coverage that mature, thin-barrier skin benefits from most.
Acne-Prone : ★★★☆☆ — GMS is moderately comedogenic at higher use levels; light formulations using it at 1–2% are better tolerated than thick, butter-heavy applications.

CONCEPT 1: Classic Nourishing Body Lotion
Usage Level : 3%
Key Ingredients: Cetyl Alcohol, Polysorbate 60, Sweet Almond Oil, Aloe Vera Juice
Result : A smooth, white O/W body lotion with excellent skin slip, balanced moisture delivery, and a clean non-greasy finish suitable for daily use.

CONCEPT 2: Rich Shea Body Butter Cream
Usage Level : 5%
Key Ingredients: Shea Butter, Kokum Butter, Jojoba Oil, Vitamin E (Tocopherol)
Result : A thick, luxurious W/O-leaning body butter cream with a melt-on-contact texture that deeply conditions dry skin and leaves a protective emollient film.

CONCEPT 3: Hair Conditioning Cream Rinse
Usage Level : 2%
Key Ingredients: BTMS-50, Cetyl Alcohol, Argan Oil, Panthenol
Result : A creamy rinse-off hair conditioner that detangles effectively, adds moisture and shine, and leaves hair feeling smooth and manageable after rinsing.

INCI Declared : Yes — must be listed on all finished product labels as Glyceryl Stearate
EU Cosmetics Reg : Permitted — Glyceryl Stearate is not listed in Annex II or Annex III of EU Regulation 1223/2009; no restriction on concentration for topical cosmetic use
Rinse-Off Limit : No limit established; standard use 1–5%
Leave-On Limit : No limit established; standard use 1–8%
Allergen Alert : No — not a recognized contact allergen; not listed in EU allergen disclosure lists
Skin Safety : Safe at recommended levels for external topical use
Eye Area Use : Use with caution — may cause mild mechanical irritation in concentrated form; generally well-tolerated in formulated eye cream products at standard levels
Ingestion : Not for internal use as a cosmetic ingredient
Pregnancy Use : Safe for topical use at standard cosmetic concentrations
Child Safety : Safe for use in baby and child care formulations at standard levels; a preferred emulsifier for sensitive infant skin products
Ventilation : Not required under normal handling conditions
Storage : Cool, dry place below 30°C in a tightly sealed container away from humidity and direct heat sources
Container : HDPE or glass; keep sealed to prevent moisture absorption and oxidation of the fatty acid component

⚠️ GMS derived from animal-source glycerol or tallow-based stearic acid is not vegan-compatible. Always confirm the origin certificate with your supplier if vegan or halal certification is required for your finished product. Self-emulsifying GMS (GMS SE) contains added alkali soaps and has different formulation behavior — confirm the grade before formulating.

Working pH Range : 4.5 – 8.0
Heat Stability : Stable up to 80°C during standard hot-process emulsification; always melt fully before combining with the water phase
Freeze-Thaw Stable : Yes when properly formulated with a complete emulsifier system
Emulsion Type : W/O when used alone; O/W when combined with a complementary hydrophilic co-emulsifier such as polysorbate 60 or ceteareth-20
Emulsification Phase: Hot — must be melted into the oil phase above 65°C before emulsification
Compatible With : Cetyl alcohol, stearic acid, polysorbate series, fatty alcohols, plant butters and carrier oils, silicones, carbomer, BTMS conditioning emulsifiers, vitamin E
Incompatible With : High concentrations of electrolytes which may destabilize the emulsion; strongly acidic systems below pH 4.0; direct combination with cationic surfactants without compatibility testing
Oxidation Risk : Low to Medium — the stearate chain has low oxidation potential but may develop a rancid fatty odor over extended storage; inclusion of 0.1% Vitamin E or BHT is recommended in oil-rich formulas
Discoloration Risk : None under normal conditions; prolonged exposure to elevated heat above 90°C may cause slight yellowing
Formulation Notes : Always melt GMS fully into the oil phase before adding the water phase. Incomplete melting results in particulate instability and grainy emulsion texture. For vegan or palm-free formulations, confirm vegetable source sunflower or rapeseed-derived GMS with your supplier.

Q: Does GMS work as a standalone emulsifier in creams and lotions?
A: Standard GMS (HLB 3.8) is a co-emulsifier and works best when paired with a hydrophilic emulsifier such as polysorbate 60 or ceteareth-20 to produce stable O/W emulsions. Used alone, it will form a W/O system or may produce an unstable emulsion in water-heavy formulas.

Q: At what temperature do I add GMS to my formulation?
A: GMS should be added to the oil phase and melted completely at 70–80°C before the water phase is introduced. Incomplete melting causes grainy or lumpy emulsion texture that cannot be corrected after the emulsion forms.

Q: What is the difference between standard GMS and self-emulsifying GMS (GMS SE)?
A: Standard GMS requires a separate co-emulsifier to produce stable O/W emulsions and has an HLB of approximately 3.8. GMS SE contains incorporated potassium or sodium stearate soaps that give it self-emulsifying capability at an HLB of around 5.5, allowing it to emulsify simple formulas without an additional hydrophilic emulsifier.

Q: Can I use GMS in cold process formulations or room-temperature mixing?
A: GMS requires heat above its melting point of 57–62°C to incorporate properly, making it unsuitable for cold process emulsion techniques. In cold process systems it will remain as undissolved wax particles that create an unstable or gritty texture in the finished product.

Q: How does GMS compare to Emulsifying Wax NF as a formulation choice?
A: Emulsifying Wax NF is a complete self-emulsifying wax blend (typically cetearyl alcohol combined with polysorbate 60 or ceteareth-20) that produces stable O/W emulsions as a single ingredient at 3–6%. GMS requires a co-emulsifier partner but gives the formulator more individual control over texture, HLB balance, and emulsion richness. GMS is preferred when building a custom multi-component emulsifier system, while Emulsifying Wax NF is more convenient for simpler beginner formulations.

Product evaluation

Review the specifications, supplied grade, intended use and compatibility of GMS (Glycerol Monostearate) Powder before ordering for production. Test a small quantity in the actual application and document the result before scaling.

Quality control

Inspect the received batch for expected appearance, odor, texture, packaging condition and labeling. Keep supplier and batch records, use accurate measurements, and retain a reference sample when the material is used commercially.

Storage and responsible use

Store tightly closed in a clean, cool and dry location away from direct sunlight. Follow the current supplier instructions and all safety, labeling and regulatory requirements that apply to the intended finished product.