CHARLOTTE GRONAN
Product manager at Stephenson

While multifunctional beauty and personal care products are not a new concept, the term has evolved to encompass the incorporation of multifunctional ingredients, such as polyglyceryl esters, into a wide range of product applications.

These powerful ingredients enable brands and manufacturers to develop multiple products using one ingredient. This is an appealing prospect when it comes to simplifying procurement, keeping less stock on site, and rationalising the production process.

When considering a multifunctional ingredient in a new beauty or skincare product formulation, whether a micellar water, cleanser, or serum, brands and formulators remain under pressure to balance ingredient functionality, sustainability, and efficiency. And although multifunctional ingredients have come a long way in terms of their application possibilities, some challenges remain. In particular, formulators often struggle to ensure product stability while meeting regulatory standards and consumer expectations, all while keeping the high performance of a product in mind. (1)

In this space, the multifunctional capability of polyglyceryl esters, derived from natural plant-based oil sources, is emerging as an indispensable component in new product formulations.

These mild, biodegradable ingredients offer three unique attributes, acting as either an emulsifier, emollient, solubiliser, or surfactant – offering a cost-effective alternative to traditional petrochemical-based ingredients. Critically, polyglyceryl esters will enable a brand to align with growing requirements for sustainable and skin-friendly formulations while still offering high-impact performance. (2)

In 2024, the global polyglyceryl esters market was valued at approximately US$0.69 billion and is on track to double, reaching US$1.54 billion by 2034. This reflects a robust annual growth rate of 8.41% from 2025 to 2034 – a signal of strong, sustained market momentum. (3)

For beauty product developers, this growth is not just a trend – it's an open invitation to innovate and explore new product formulations. As consumer demand for natural, sustainable, and multi-functional performance ingredients intensifies, polyglyceryl esters are uniquely placed to deliver. Their ability to enhance emulsification, improve product texture, and boost skin compatibility makes them a powerful tool when developing next-gen formulations that meet both eco-conscious and efficacy-driven expectations.

For brands and formulators looking to future-proof their offerings by moving away from synthetic and artificially derived ingredients, now is the time to explore polyglyceryl esters. They truly can bring a new level of product innovation strategy, differentiation, and long-term growth. (4)

The ability of polyglyceryl esters to stabilise complex emulsions represents a major advancement in modern skincare and personal care formulation. But what makes them so unique? One aspect is their effect on product stability.

In the past, creating stable emulsions in both water-soluble and oil-soluble actives has been a challenging balancing act. This is because the chemical structure of an emulsion is inherently thermodynamically unstable, with a tendency to separate over time. Several factors can contribute to formulation instability, including the creaming, flocculation, and coalescence of different ingredients in a formulation. This makes careful formulation and processing to maintain stability important, and one of polyglyceryl esters strongest unique selling points.

Until recently, creating a stable emulsion often involved using multiple ingredients to solubilise, stabilise or enhance performance. While effective, this approach can add complexity to formulations, with potential implications for cost, irritancy, and stock management.

As polyglyceryl esters are emulsifiers, their main function is to improve emulsion stability. Interfacial tension graphs commissioned by Stephenson indicate that the tension between water and oils used is reduced when a polyglyceryl ester is added. This allows the creation of a thick, stable emulsion by just adding water, oil, and polyglyceryl-4 Oleate for example.

Another benefit to using polyglyceryl esters in multifunctional formulations is its wide hydrophilic-lipophilic balance (HLB), which affects the intended function of a product. HLB refers to the numerical scale (0 – 20) of a surfactant’s ability to attract either water or oil. Surfactants are typically compounds that reduce the surface tension between liquids, used in the creation of emulsions.

The distinctive structure of polyglyceryl esters means that they are both hydrophilic (water-loving) and lipophilic (oil-loving). This amphiphilic nature enables these esters to effectively bridge water and oil phases, creating stable, uniform emulsions that can incorporate a diverse range of often expensive active ingredients and fragrances - without separation or degradation.

For example, a low HLB, typically between 4 to 6, such as those found in polyglyceryl 4-oleates, are more lipophilic and better suited for water-in-oil emulsifiers where water droplets are dispersed in oil.

When we look at the other end of the scale and a higher HLB, typically between 15-18, such as those found in polyglyceryl-10 Caprylates, these are more hydrophilic and, therefore, suitable for oil-in-water emulsions. When used as a solubiliser, it makes the inclusion of oil-based fragrances and or essential oils much easier in the formulation mix.

In addition, there are other significant benefits to using polyglyceryl esters in formulations:

1. Formulation freedom & innovation

With the growing demand for multi-functional products such as serum-moisturiser hybrids, tinted sunscreens, or cleansing balms that both hydrate and treat, the ability to seamlessly incorporate both oil- and water-based ingredients opens new doors for innovation. Actives like niacinamide (water-soluble) and retinol (oil-soluble), for example, can now coexist in a single, elegant formulation without the typical compatibility challenges.

2. Improved aesthetic & sensory profile

Polyglyceryl esters also contribute to the final texture, feel, and spreadability of products, ensuring emulsions are not just stable but also pleasant to use. This is crucial, as consumer preference often hinges on sensorial experience as much as efficacy.

As polyglyceryl esters are non-ionic, they offer thickening and rheology properties that can contribute to the viscosity and structure of emulsions. In particular, their thickening effects are due to the hydrophilic-lipophilic balance. Depending on the chain length of the fatty acid and the degree of polymerisation of the polyglycerol as a higher polyglycerol content will increase water affinity which can promote gel-like networks in water-rich systems.

Polyglyceryl esters can also self-assemble into liquid crystalline structures, forming either lamellar or hexagonal liquid crystalline phases, especially in oil-in-water (O/W) emulsions. These structures trap water and oil within ordered domains, which leads to increased viscosity and contributes to a rich, cushiony texture. When interacting with other emulsion components, polyglyceryl esters can interact synergistically with fatty alcohols, waxes, or thickeners such as xanthan gum, reinforcing the structure and yielding thicker, more stable emulsions.

Unlike some traditional emulsifiers or thickeners such as carbomers or high-molecular-weight silicones, polyglyceryl esters often impart a light, smooth, and non-tacky finish, making them ideal for facial moisturisers, lotions, and sunscreens. Lastly, by stabilising the oil-in-water interface and reducing droplet coalescence, polyglyceryl esters help maintain a uniform product appearance and texture over time.

3. Cleaner labels, fewer ingredients

One polyglyceryl ester can replace multiple emulsifiers or stabilisers, which supports the formulation of minimalist, clean-label products - a growing consumer demand. This reduction in total ingredient count also simplifies regulatory compliance and speeds up product development cycles.

4. Support for green & sustainable formulation

Being non-ionic, plant-derived, and biodegradable, polyglyceryl esters align with the shift toward eco-conscious formulation practices while offering reliable performance—something that’s often hard to achieve with traditional natural emulsifiers.

In the past couple of years, the industry has witnessed a shift towards more sustainable and natural products.

This will continue to drive increased dedicated research for sustainability-produced ingredients and cosmetics, including polyglyceryl esters. As this conversation grows, developers of skincare and beauty ingredients must answer requirements for targeted multifunctional products that align with the skinimalism and hybrid beauty ethos.

Here, polyglyceryl esters are a great choice: Their versatility and multifunctionality can significantly reduce ingredient and formulation complexity that could enable a cleaner INCI list, simplify procurement and transformation, and reduce regulatory complexities. (5)

Another benefit is the low interfacial tension of polyglyceryl esters. This means that these products can effortlessly blend at room temperature, allowing for cold-process creations. Lowering the processing temperature at which a beauty and skincare product is produced reduces energy consumption in a plant. This has a dual function: resulting in reduced costs, but critically, lower temperatures can help preserve the integrity of heat-sensitive ingredients for enhanced product efficacy.

Modern manufacturing aims to create polyglyceryl esters using green principles, with minimal environmental impact. There are several benefits to this process: Esterification can offer a solvent-free reaction, often uses renewable feedstocks, and is a low-energy and efficient process.

Traditional esterification typically involve organic solvents which are either volatile or environmentally hazardous, green processing eliminates these by using melt-phase reactions. This refers to the process where both polyglycerol and fatty acids or oils are heated to react in their liquid state – reducing volatile organic compounds, waste, and energy used in solvent recovery.

In terms of renewable feedstocks, polyglycerol is made from glycerol, a by-product of biodiesel and soap production, making it a waste-derived, renewable raw material. In addition, fatty acids are typically obtained from vegetable oils such as coconut, rapeseed or palm-free sources which are biodegradable and plant-based.(6)

Lastly, vacuum-assisted processing can drive esterification forward by removing water, increasing efficiency without the need for high temperatures which also supports cold processable emulsifiers, reducing energy use during product formulation.

As demand for multifunctional and sustainable beauty ingredients and the science to develop them grows, this will positively impact advancements in biotechnology and green chemistry. In addition, formulations driven by AI tools could assist brands in optimising ingredient compatibility. This could have a far-reaching impact on challenges such as predicting stability outcomes, resulting in many downstream benefits during product development.

The ability to personalise products to a consumer’s unique skin needs is also on the up, with many brands exploring multifunctional formulations that are tailored to individual skin concerns through data-driven diagnostics.

Meanwhile, sustainable ingredient innovation, including upcycled actives, using renewable resources and carbon-negative raw materials will impact the sustainability and circularity of the beauty economy.
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But what does it mean for formulators and brands? The ability to stay ahead in the multifunctional beauty space will require a careful balance of science, sustainability, and strategic ingredient sourcing. By leveraging multifunctional, natural-based technologies and rethinking traditional formulation approaches, the beauty and personal care industry can push the boundaries of innovation while meeting evolving consumer demands.