Glyceryl Stearate Citrate is a chemical compound, fatty acid monoglyceride, formed from glycerine, stearic acid (generally from soybean, rapeseed, canola and maize oils) and citric acid, glycerol stearate ester of citric acid and stearic acid. It is a monoglyceride of fatty acids of vegetable origin but esterified and therefore not 100 per cent natural. Anionic.

Glyceryl Stearate Citrate is an emulsifier commonly used in cosmetics and personal care products. It is derived from plant-based sources, such as vegetable oils, and is used to help blend water and oil-based ingredients in formulations. Known for its ability to improve the texture and stability of cosmetic products, Glyceryl Stearate Citrate also functions as a skin-conditioning agent, making it a versatile ingredient in skincare and haircare products.

Chemical Composition and Structure

Glyceryl Stearate Citrate is formed from the esterification of glycerin, stearic acid, and citric acid. The combination of these components results in an ingredient that serves as a mild emulsifier and stabilizer. Glycerin, known for its hydrating properties, is combined with stearic acid (a fatty acid) and citric acid to create a compound that helps emulsify and soften the skin.

Physical Properties

It is usually a white to off-white, waxy solid. It is oil-soluble but can disperse well in water when used in emulsions, making it ideal for use in lotions, creams, and other emulsified products. Its ability to blend and stabilize oil-in-water emulsions ensures a smooth, uniform texture in cosmetic formulations.

Production Process

The production of Glyceryl Stearate Citrate involves the esterification of glycerin (derived from vegetable oils) with stearic acid and citric acid. The process results in a stable emulsifying agent that can be used in various cosmetic formulations to help mix oil and water-based components, creating a smooth and homogenous product.

It appears as a white powder suitable for the production of oil/water emulsions, insoluble and dispersible in hot water, soluble in oil at high temperatures. Easily hydrolysed under conditions of strong alkalis or strong acids.

What it is used for and where

Cosmetics

• Skin conditioning agent - Emollient. Emollients have the characteristic of enhancing the skin barrier through a source of exogenous lipids that adhere to the skin, improving barrier properties by filling gaps in intercorneocyte clusters to improve hydration while protecting against inflammation. In practice, they have the ability to create a barrier that prevents transepidermal water loss.  Emollients are described as degreasing or refreshing additives that improve the lipid content of the upper layers of the skin by preventing degreasing and drying of the skin. The problem with emollients is that many have a strong lipophilic character and are identified as occlusive ingredients; they are oily and fatty materials that remain on the skin surface and reduce transepidermal water loss. In cosmetics, emollients and moisturisers are often considered synonymous with humectants and occlusives.
• Surfactant - Emulsifying agent. Emulsions are thermodynamically unstable and are used to soothe or soften the skin and emulsify, so they need a specific, stabilising ingredient. This ingredient forms a film, lowers the surface tension and makes two immiscible liquids miscible. A very important factor affecting the stability of the emulsion is the amount of the emulsifying agent. Emulsifiers have the property of reducing the oil/water or water/oil interfacial tension, improving the stability of the emulsion and also directly influencing the stability, sensory properties and surface tension of sunscreens by modulating the filmometric performance.
• Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Used as an oil/water emulsifier with medium/low viscosity even for PEG-free formulations and with an optimal oil-phase concentration of 25-35%. Possesses high hydrophilic-lipophilic balance (HLB) 

Acts as a non-ethoxylated hydrophilic emulsifier and as a co-emulsifier for PEG-free formulations. Anionic surfactant, softening agent for softening skin, skin conditioner and fragrance (1), also for sensitive skin. It has the function of helping skin and hair retain moisture and tends to form a gel system in the aqueous phase of the emulsion. Emulsifiers have the property of reducing interfacial tension and also directly influence the stability, sensory properties and surface tension of sunscreens by modulating their filmometric performance. 

Dosage: Glyceryl Stearate Citrate is included in cosmetic formulations in percentages between 0.25%, 2% (improves viscosity of rinse-off products that have difficulty thickening with sodium chloride) and 4%. When added to hot water it is not soluble, but must be stirred to obtain a cloudy liquid ready for emulsification.

Food

Emulsifier, fragrance.

Other uses

Double emulsions are promising delivery vehicles for the protective and programmed release of bioactive compounds. In the digestive phase Glyceryl Stearate Citrate forms a kind of crystalline shell and has been shown to decrease the rate of intestinal lipid digestion in the oil/water emulsion (2).

Safety. The purity level of commercial monoglyceric monoester is about 90 per cent, and impurities include fatty acids, monoglyceric diesters, mono-, di- and tri-glycerides.

Safety in Use
Glyceryl Stearate Citrate is considered safe for use in cosmetic products. It is non-irritating, non-toxic, and generally well-tolerated by the skin, making it suitable for sensitive skin types. Its plant-derived components and mild emulsifying properties make it a popular choice in natural and organic cosmetic formulations.

Allergic Reactions
Allergic reactions to Glyceryl Stearate Citrate are rare. It is a gentle ingredient, and its plant-based origins make it less likely to cause irritation. However, as with any cosmetic ingredient, individuals with sensitive skin should perform a patch test before using products that contain it.

Toxicity and Carcinogenicity
It has been thoroughly evaluated for safety and is approved for use in cosmetics and personal care products at concentrations that are considered safe for consumers.

Environmental and Safety Considerations
Glyceryl Stearate Citrate is biodegradable and does not pose significant environmental risks. It is derived from renewable, plant-based sources, making it an eco-friendly choice in cosmetic formulations.

Regulatory Status
Glyceryl Stearate Citrate is approved for use in cosmetics and personal care products by regulatory bodies such as the European Union and the Food and Drug Administration (FDA) in the United States. It is regulated to ensure safe use in a wide range of cosmetic formulations.

For more information:

Glyceryl Stearate Citrate studies

Typical commercial product characteristics Glyceryl Stearate Citrate

Appearance	White powder
pH	5.5-8.0
Boiling Point	>260°C (500°F)
Melting Point	58-64°C (136.4-147.2°F)
Acid value	0,00-20,00 mg KOH/g
HLB value/range	12
Shelf life	2 Years
Storage	dry place, protected from direct sunlight, heat
Chemical safety

Prezzo

100g    $5

• Molecular Formula   C₂₈H₅₄O₁₂    C₂₃H₄₆O₆
• Molecular Weight      582.7
• Exact Mass   582.361511
• CAS    39175-72-9    55840-13-6   86418-55-5
• UNII    WH8T92A065
• EC Number   259-855-5
• DSSTox Substance ID  DTXSID00204440
• IUPAC  3-(carboxymethyl)-3-hydroxypentanedioic acid;octadecanoic acid;propane-1,2,3-triol
• InChl=1S/C18H36O2.C7H10O7.C3H8O3/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20;8-4(9)1-7(14,2-5(10)11)3-6(12)13;4-1-3(6)2-5/h2-17H2,1H3,(H,19,20);14H,1-3H2,(H,8,9)(H,10,11)(H,12,13);3-6H,1-2H2
• InChl Key      HFJHNGKIVAKCIW-UHFFFAOYSA-N
• SMILES   CCCCCCCCCCCCCCCCCC(=O)O.C(C(CO)O)O.C(C(=O)O)C(CC(=O)O)(CC(=O)O)O
• ChEBI  176146 

Synonyms:

• 3-(carboxymethyl)-3-hydroxypentanedioic acid;octadecanoic acid;propane-1,2,3-triol
• Stearyl monoglyceridyl citrate
• 1,2,3-Propanetricarboxylic acid, 2-hydroxy-, ester with 1,2,3-propanetriol monooctadecanoate
• Monostearin citrate
• Glycerol stearate citrate

References_____________________________________________________________________

(1) Cefali, L. C., Ataide, J. A., Fernandes, A. R., Sousa, I. M. D. O., Gonçalves, F. C. D. S., Eberlin, S., ... & Gava Mazzola, P. (2019). Flavonoid-enriched plant-extract-loaded emulsion: a novel phytocosmetic sunscreen formulation with antioxidant properties. Antioxidants, 8(10), 443.

Abstract. The aim of this study was to develop a phytocosmetic sunscreen emulsion with antioxidant effect, containing a blend of flavonoid-enriched plant extracts. In vitro sun protection factor, antioxidant activity, skin irritation, photostability, cutaneous permeation, and retention of flavonoids were evaluated. Thermodynamically stable emulsions were obtained and tested for sensorial analysis after loading the blend of extracts. The selected emulsion was stable when stored at low temperatures (5 C), for which after 120 days the concentration of quercetin and rutin were above their limit of quantification, i.e., 2.8 ± 0.39 µg/mL and 30.39 ± 0.39 µg/mL, respectively. Spreadability, low rupture strength and adhesiveness were shown to be similar to a conventional topical product. Higher brittleness, pseudo-plastic, and viscoelastic behaviors were also recorded for the developed phytocosmetic sunscreen. The product presented a critical wavelength of 387.0 nm and ultraviolet rays A and B (UVA/UVB) rate of 0.78, confirming that the developed formulation shows capacity for UVA/UVB protection, protecting skin against damages caused by Ultraviolet (UV) radiation. Rutin was shown to permeate the skin barrier and was also quantified in the stratum corneum (3.27 ± 1.92 µg/mL) by tape stripping and retention test (114.68 ± 8.70 µg/mL). The developed flavonoid-enriched phytocosmetic was shown to be non-irritant to skin by an in vitro assay. Our results confirm the antioxidant activity, sun protection, and physical properties of the developed phytocosmetic for topical application.

(2) Li, W., Wang, W., Yong, C., Lan, Y., Huang, Q., & Xiao, J. (2022). Effects of the Distribution Site of Crystallizable Emulsifiers on the Gastrointestinal Digestion Behavior of Double Emulsions. Journal of Agricultural and Food Chemistry, 70(16), 5115-5125.

Abstract. Double emulsions (DEs) are promising delivery vehicles for the protective and programmed release of bioactive compounds. Herein, DEs with monoglycerides crystallized at the internal- or external interface or oil phase were fabricated. The results suggested that the crystallization site of monoglycerides exerts a significant role in retarding the structural degradation and lipid digestion of DEs by affecting the available contact area of lipase. At the initial stage of intestinal digestion, compared with noncrystalline DEs (82.1%, 3.7 min), the burst release of internal markers in the internal interface crystallized emulsions was decreased by 42.4% and the lag time of free fatty acid (FFA) release was delayed by 5.8 min in the external interface crystallized emulsions. The structural integrity and digestion kinetics of the external interface crystallized DEs were synchronized with the retention time of the interfacial crystals. Therefore, crystallizable emulsifiers exhibit unique and fine regulatory effects on the digestive properties of emulsions.