Silverson x Beauty Science Labs: Mixing Innovation in Cosmetic Formulation

Every luxurious face cream, every crystal-clear gel, every velvety lotion begins with the same challenge: combining ingredients that don’t naturally want to come together. How do professional formulators overcome this hurdle to create consistent, commercially viable products?

That’s exactly what Silverson Machines set out to demonstrate in partnership with Beauty Science Labs. In a series of hands-on demonstration videos filmed at Silverson’s Customer Resource Centre—what Technical Sales Engineer James Cardus calls “our indoor mixing playground”—Beauty Science Labs’ Principal Chemist Tumi Siwoku reveals the techniques and technology behind professional-grade cosmetic formulation.

A Partnership Built on Experience

For Tumi, a veteran formulator, Silverson equipment has been integral from the start.

“[Silverson] became a firm favorite when it came to emulsifying and creating new products because of the ease of use and how we were able to scale from lab to production with great ease.”

Together, Tumi and James explore two fundamental cosmetic bases, a Hot Process Emulsion and a Cold Process Gel, demonstrating how Silverson Laboratory Mixers deliver the precision and control that turn good formulations into consistently great products.

Hot Process Method: Creating Stable Creams and Lotions

For many cosmetic formulations, the hot process method is essential, particularly when creating creams and lotions. By using controlled heat and precise mixing, this method successfully transforms two opposing elements, oil and water, into a cohesive, stable emulsion.

Monitoring Temperature for Optimal Formulation

Before emulsification can occur, any waxes must be heated until fully melted and combined with any other ingredients in the oil phase. This typically happens around 70 °C (158 °F). The water phase is warmed to a similar temperature so both phases meet evenly, allowing them to combine without separating or shocking the mixture.

At this stage, the Silverson High Shear Laboratory Mixer plays a critical role. Its rotor/stator workhead generates intense shear, instantly dispersing the oil phase into the water phase to form a fine, uniform emulsion. After a stable base has formed, the batch is allowed to cool gradually. As the temperature falls, viscosity builds and the emulsion structure stabilizes.

“We all know that oil and water don’t mix,” Tumi explains. “Once there is an emulsifier within the oil phase, the Silverson allows us to homogenize and bring the two phases together.”

Silverson Laboratory Mixers can also be fitted with a temperature probe that sits alongside the workhead directly in the product, with a digital readout on the head unit. This allows formulators to monitor temperature in real time throughout heating and cooling, critical for ensuring sensitive ingredients are added at precisely the right moment.

“The [Silverson] temperature probe is amazing because it allows us to understand the internal temperature of the system. And once it’s at the relevant temperature, we can then have that confidence to add all our preservatives, our fragrances.”

Once the temperature drops below 40 °C (104 °F), formulators can safely incorporate the final components that define the product’s character: its fragrance, color, preservatives, and botanical extracts. Adding these ingredients too soon can compromise both performance and appearance:

• Evaporation: Fragrance oils and volatile extracts (especially those containing alcohols, esters, or essential oil components like limonene or linalool) can evaporate when added at high temperature. This can diminish scent strength or even remove it entirely.
• Degradation: Elevated temperatures can denature or oxidize active ingredients such as vitamins (e.g., vitamin C, panthenol, niacinamide) and can destabilize preservatives like phenoxyethanol or certain parabens. The result is reduced performance or shortened shelf life.
• Color Change: Many cosmetic colorants, particularly natural pigments and dyes, are heat-sensitive. Overheating can cause oxidation or pH shifts that alter hue or reduce vibrancy.

Careful temperature control at this stage is key to preserving the integrity of these ingredients and achieving consistent results. With accurate temperature monitoring and the high shear efficiency of Silverson mixers, formulators can carry out a successful hot process method that delivers smooth, stable emulsions and repeatable results, giving confidence that each product will look, feel, and perform exactly as intended.

Cold Process for Crystal-Clear Gels

Unlike emulsions that require heating and cooling, gel formulations are built at ambient temperature. Some gels use polymers that thicken through simple hydration while others, like the pH-sensitive system demonstrated here, respond to chemical activation to develop viscosity. This cold process approach is the standard method for creating gels and surfactant systems like body washes and shampoos.

Mixing Techniques for Gel Formation

In this demonstration, Tumi uses a pH-sensitive copolymer, which responds to the alkaline addition of a 10% sodium hydroxide solution to thicken the gel. Achieving the right viscosity and clarity is a delicate balancing act; too little shear and the polymer won’t fully activate, too much and unwanted air can become trapped in the system.

This critical factor highlights the importance of controlled mixing to avoid aeration, which can cloud an otherwise clear product. As Tumi notes:

“If we have the speed of our homogenizer up too high, we find that the air bubbles get trapped into the system, and then we have an aerated gel which affects the clarity.”

With its infinitely variable speed control, the Silverson Laboratory Homogenizer Mixer gives formulators the fine-tuned control needed to strike that balance. The result is a smooth, crystal-clear gel ready for final customization with actives, fragrances, or colorants. With the right technique and Silverson’s precision control, formulators can achieve this level of clarity and consistency every time.

Shared Expertise in Formulation and Mixing

This collaboration highlights not only the capabilities of Silverson mixers but also the value of bringing formulation chemists and process engineers together. As Tumi reflects:

“There are so many different variables and factors that we can consider, and I really enjoy that Silverson have considered those things, which makes my scale up process so much easier.”

Whether you’re developing skincare, haircare, personal care formulations, or other cosmetic applications, these demonstrations show how the Silverson Laboratory Mixer provides the precision and power needed to achieve consistent results with ease.

A big thank you to Tumi Siwoku for sharing her time, expertise, and insights, and for helping us showcase what’s possible when formulation and mixing innovation come together.