A new era of healthy fats

There are no doubts that solid and semisolid fats are fundamental ingredients able to confer sensory properties like mouthfeel, texture, flavour, and structural building up in many food products¹. The remarkable qualities of these fats are linked to their ability to form solid, crystalline structures at room temperature due to the presence of saturated fatty acids¹. Unfortunately, their excessive dietary consumption, as it happens in developing and developed countries, correlates with obesity, cardiovascular diseases, metabolic syndrome, and type 2 diabetes². These non-communicable diseases are the leading causes of death around the globe and are causing extensive burden on the public healthcare system1-7

One of the most promising solutions for substituting saturated fats and reducing the risk of developing cardiovascular diseases, along with possibly improving individual wellbeing, and reducing healthcare costs are oleogels³.Oleogels are semi-solid lipid-based materials containing > 70% of oils rich in unsaturated fatty acids physically entrapped either in a crystalline/polymer network or a scaffold built of biopolymers or particles (called gelling or structuring agents). Fig. 1 shows an example of the visual appearance of two oleogels structured using ethylcellulose and sunflower wax.

Even though oleogels have shown promising results as fat replacers in several food products on the lab scale, the fat-to-oleogel transition is still not materialising, contrarily to the shift from animal to plant proteins that we are witnessing. Regulatory hurdles, cost of production, sustainability of production methods, limited resistance to shear forces, and storage instability have been the key factors hindering oleogels from becoming the ‘fat of the future’.

Our group has dedicated considerable efforts to enable this transition during the past few years. Identifying, addressing, and devising solutions for the key challenges associated with the shift from fats to oleogel, ultimately propelled us into the foundation of Perfat Technologies Ltd., a company that is commercialising and bringing the benefits of our oleogel-based technology to the society.

This article begins by exploring the latest research conducted at the University of Helsinki in the fields of Food Science, Materials Physics and Engineering, and Ultrasonics. The second part delves into the narrative, mission, vision, products, and individuals behind Perfat Technologies. Our ongoing technological advancements aim to pave the way for a new era of oleogels, potentially revolutionising the substitution of saturated fats in various food products.

In envisioning industry's shift from traditional fats to oleogels, the first crucial step involved identifying the most promising oleogel production method that will ensure a practical transition. As a first step, we developed a new classification of oleogelation methods by analysing and clustering 200+ methodologies reported in the literature by using three key factors: (i) the heat used during oleogel production, (ii) the electrical energy consumption throughout the oleogelation process, and (iii) the time required to form oleogels. These three factors are fundamental to respectively understanding (i) the oxidative/storage stability of the resulting oleogel, (ii) sustainability, upscaling feasibility, and the overall cost of oleogelation, and (iii) costs and considerations regarding warehouse storage. Our results showed that oleogel preparation approaches can be classified into low-, medium-, and high-input methods, where the low-input approaches emerged as the most relevant methods for starting the fat-to-oleogel transition (Fig. 2)⁴.

Upon identifying the optimal oleogel production method, we addressed a neglected concern: their high caloric content. Despite having a superior nutritional profile compared to fats, oleogels often contain dense lipids and are generally fully digestible, contributing to the risk of obesity and related non-communicable diseases through potential overconsumption. For this reason, our group set off to devise oleogels with customisable lipid digestibility that also preserve their structural functionality. To rapidly progress with this research, we used the standardised static in vitro gastrointestinal digestion simulation, INFOGEST protocol, which mimics human digestion at lab scale. However, we realised that this standardised protocol proved to be inadequately designed for simulating the digestion of high-fat foods and oleogels. After studying the problems of this protocol, we specifically adapted it for reliably simulating the digestion of oleogels. The modified method was assessed and validated through advanced analytical chemistry methods⁵. Using the modified INFOGEST protocol, we explored the lipolysis mechanisms of oleogels based on ethylcellulose and wax, shedding light on the different lipolysis mechanisms involved in their digestion⁵.

To tackle the full digestibility of the most promising oleogels, we developed two engineered oleogels with tailorable digestibility, namely ‘oleogel-in-oleogel’ and ‘encapsulated oleogel-in-oleogel’ systems, where an oleogel or an encapsulated oleogel (inner oleogel) is dispersed into a second outer oleogel (Fig. 3). By adjusting the ratio of inner to outer oleogels, we could modulate the digestibility of our new engineered oleogel, as demonstrated, using our modified in-vitro digestion protocol.

The promising results obtained from this approach resulted in the filing of a patent application (WO2023037053A1), and the outcomes are currently under review for publication. In the first approach, the inner oleogel is shaped in the form of microbeads, gelled by ethylcellulose, dispersed inside another oleogel. Ethylcellulose oleogels are known to have a reduced digestibility⁵, and dispersing these oleogels as beads offers an advantageous control over oil digestibility at lower ethylcellulose concentrations, along with the fact that ethylcellulose acts like a dietary fibre, inducing satiety. In the second approach, the inner oleogel is encapsulated using wall materials to form a powder. In an early version of this system, we used cellulose nanocrystals to coat oleogel droplets, which resulted in a great suppression of oleogel digestibility. However, incorporating these nanomaterials posed a challenge in the formulation, potentially hindering widespread consumer acceptance. Therefore, the original system underwent modifications, retaining the ability to tailor digestibility, while employing only ingredients commonly used in the food industry. The result was an encapsulated oleogel-in-oleogel that has a controllable lipid digestion extent from 54.1% to 96.4% compared to the constituting oil, along with around 80% less saturated fatty acids and 5.9 – 29.3% fewer calories than coconut oil, and inclusion of 7.3 – 36.6% health-promoting fibres. In addition, the resulting system can also be considered as a reinforced composite material where the oleogel is reinforced with the addition of solid particles that act as a co-structurant, creating a hybrid network in conjunction with the crystalline gelator.

We conducted in vivo studies on 118 mice, providing two diets with oleogels, oils, and lard as lipid sources. Preliminary findings indicate that the dietary oleogel proportion significantly influences mice weight gain and food consumption, being more important than the specific oleogelator used.

The mechanical properties of oleogels are governed by the microscopic crystal network of the structuring agent. In oleogel fabrication, processes like temperature modulation, shear mixing, and ultrasound (US) can be applied. By manipulating these processes, we can modify the structuring-agent crystal-network topology to develop oleogels with specified mechanical and sensory properties. For this purpose, we developed a mathematical model that connects the macroscopic mechanical properties to the microscopic crystal network. Such micro-to-macro models have been previously used to engineer properties of cheese⁶. With a robust mathematical model, we can optimise crystal networks to achieve desired mechanical and sensory properties. To alter the structuring material's crystal network for desired oleogel mechanical properties, we use complex US pressure fields in the form of US standing waves. This technique tailors the crystal network during crystallisation due to the mechanical effect of US waves, resulting in a heterogeneous distribution of lipid crystals and varying structuring material concentrations. The use of acoustic pressure fields for crystal network control was first demonstrated and studied by our group⁷, and resulted in a filed patent application (US20210127720A1).

Figure 4 illustrates the key components of our mathematical model, integrating acoustic and oleogel mechanical property modelling. We start by defining the crystal network topology in an idealised sample (Fig. 4A) with mechanical properties meeting the specifications. Based on the found spatial distribution of crystal density (Fig. 4A and 4A1), the inverse problem of finding the necessary US field that rearranges the density of crystals accordingly is solved⁸. The found US field is a superposition of US beams (Fig. 4B) with different parameters generating US standing wave (Fig. 4B1) in the area where the treated material is placed. The next step is to simulate the movement of growing crystals in the US standing waves during the formation of the oleogel. The task is to find the required sonication time, to minimise the difference between the calculated pattern of the crystal density and the density of the idealised pattern. Figs. 4C and 4D show two crystal density distributions of an oleogel when the non-optimal (Fig. 4C) and the optimal time (Fig. 4D) of sonication is applied. Finally, the full-size sample model is ready (Fig. 4D), which is converted into a Finite Element Method (FEM) model in the COMSOL Multiphysics software for calculating the mechanical properties.

For an accurate full-size sample simulation, we must examine how the mechanical properties of the oleogel are affected by the structuring agent crystal network at different mass fractions. Achieving the most representative mechanical model involves imaging the microstructure of oleogels using phase-contrast X-ray microtomography. We then calculate the mechanical properties of the oleogel microstructure. The calculation is based on FEM, where the three-dimensional microstructure is divided into tetrahedral mesh elements as shown in Fig. 4E. The calculation reveals the distribution of mechanical stress and strain in the crystal network as shown in Fig. 4F. In the calculations, the structuring material is described using advanced material models from polymer physics⁹. To our knowledge, this novel modelling method for 3D oleogel microstructure has not been published before. Using our model, we can essentially do virtual experiments, which predict the results of shear measurements performed by a rheometer or compression measurements performed by a texture analyser. Therefore, the simulation yields specific mechanical values that uniquely characterise the oleogel at various mass fractions of the structuring agent. Using the result of US modelling a full-sized oleogel model suitable for FEM modelling is prepared. For this purpose, each point of the US model is substituted with a homogeneous material having mechanical quantities equivalent to the oleogel of the corresponding crystal concentration. This new model is used to calculate the mechanical parameters of the sample patterned with US.

For the validation of the mathematical model, US treatment chambers for one- and two-dimensional structure formation are developed (Fig. 4G). For reproducibility and to analyse the impact of temperature modulation on crystal network formation during US treatment, chambers are fitted with an in-house automated temperature control system. This system allows systematic control of the cooling profile during sample treatment, influencing the optimal timing for sonication.

Most oleogels have a limited resistance to shear forces, leading the oleogel to lose its mechanical properties. To overcome this problem, we took a different approach by developing oleogels using, as structuring materials, only ultrasonically enhanced electrospun fibres¹⁰. Ultrasound-enhanced electrospinning (USES) is a needleless, open-surface electrospinning method developed at the University of Helsinki, which uses one or multiple focused ultrasound transducers to produce nano-and microfibers whose average diameter can be changed on-the-fly by changing the ultrasonic actuation parameters¹¹. To obtain a proof-of-concept oleogel, we electrospun polyethylene oxide (PEO), a common non-toxic polymer, and added it at 10% and 20% concentration to rapeseed oil, walnut oil, and flaxseed oil which have increasing levels of unsaturation, respectively. Oleogels were obtained after cryo-milling the mixture to partially break the entangled USES fibres and obtain a paste like material that possessed good resistance to shear forces and a great thixotropic recovery¹⁰ (Fig. 5). From this proof-of-concept approach we advanced our research and developed oleogels by using electrospun gelatin, dextran, or starch fibres added to oils and milling the resulting mixture at room temperature. These oleogels have similar rheological properties to those obtained with PEO but the concentration of fibres used could be reduced to 5%. These results led to the filing of a patent application (WO2024003446A1).

Building on our innovations developed at the University of Helsinki over the last years, Perfat Technologies was founded in June 2023, with the vision and mission of establishing itself as a leading global B2B supplier of healthy fats and associated technology solutions. Perfat Technologies’ scientific foundation is built on the research conducted by our diverse, highly talented team of seven nationalities. Supported by commercialisation funding from Business Finland (Oleoflow project), the team was further strengthened with commercial experts to reach the perfect line-up for a spin-out (Fig. 6).

The research team was initially motivated to enhance the nutritional profile of common foods, understanding the potential preference for modifying existing eating habits rather than completely altering them. Fat is one of the three essential macronutrients that we all need to be able to function properly. At the same time, we are overconsuming saturated fats which are associated with various diseases, including cardiovascular diseases, the leading cause of death globally with over 17 million deaths attributed to it annually¹². Compared to research on carbohydrates, sweeteners, and alternative proteins, fats have received notably less focus. Recognising this gap, our interdisciplinary team combines expertise in food science and material physics to innovate in the development of healthier and more sustainable fat alternatives to traditional options like palm oil, coconut oil, and butter. Perfat Technologies focuses on converting liquid (healthy) oils into functional solid and semi-solid fats using material physics principles to create oleogels, preserving the oil's chemical composition without resorting to any chemical processes. Our mission stands upon three primary pillars:

Health – focusing on improving cardiovascular and gut health while also contributing to the reduction of obesity epidemic;

Functionality – built on developing products capable of matching the performance of any type of fats employed in the food industry along with the ability to work with the most common manufacturing processes in the food industry (e.g., mixing, pumping, homogenisation, pasteurisation, and sterilisation), and its unique ability to self-restructure during processing to best accommodate the intended use;

Sustainability – Focused on locally sourced ingredients, available equipment, and efficient methods, we prioritise minimal inputs (raw materials, energy, time) to achieve desired functionality. Our solutions integrate into existing food products, ensuring a smooth fat replacement without requiring adjustments to customers’ production lines or incurring additional capital and operational costs.

The company got initial financial backing from the University of Helsinki and Big Idea Ventures (‘BIV’), one of the most active food tech investors globally. By leveraging contacts initiated already prior to the spin-out and BIV's network, the company was quickly able to establish many promising relationships with both local and multinational food producers to test Perfat's fat solutions in real food applications. An example of Perfat's healthy fat ingredient and its application in chocolate pralines is shown in Fig. 7. Based on positive feedback, the company initiated commercial pilot projects and aims to commence full-scale production by the end of 2024.

The seed for maintaining a long-term novelty edge in the competitive landscape lays in strong and constantly evolving research. Strong R&D is in Perfat Technologies heritage, and the company is actively strengthening its IP portfolio that already contains 4 patent application families. The core Perfat products are oleogel-based fats that combine health with uncompromised structure and applicability. Furthermore, the company is innovating to provide differentiated and tailored fat solutions. This involves engineering the fat's digestion profile through a novel encapsulation approach and optimising structure by spatially controlling particle positioning with acoustic pressure fields. Perfat's core product has 80% less saturated fatty acids than coconut or palm oils, and up to 25% fewer calories than traditional fats. On top of that, the newly developed fat contains up to 30% dietary fibres and contains no water as well as being highly tailorable; it is suitable for most food applications where solid or semi-solid fats are needed to provide the desired texture and mouthfeel to a food application. As the product is crafted using readily available ingredients, it does not necessitate novel food approvals from the EU.

As of early 2024, the Perfat Technologies team consists of 7 FTEs representing four different nationalities. The team members are the core founders, Jyrki Lee-Korhonen, Dr Fabio Valoppi, and Anton Nolvi, supported by a highly talented R&D team of Dr Saman Sabet (food science), Dr Satu Kirjoranta (food science) and Afsane Kazerani (food tech), and Marcello Basset (B2B sales). In addition, the team is supported by five Senior Advisers and/or part-time employees, including four PhDs. Upon reaching industrial scale, we expect to be able to deliver our innovative fats at price levels competitive with traditional solid fats.

The shift from traditional to alternative fats is underway, and we stand at the forefront of this transition. Our pioneering oleogel research at the University of Helsinki explores tailored digestibility, shear resistance, and the perfecting of crystal network formation, setting the foundations for Perfat Technologies. By standing at the intersection of food science, material physics, and ultrasonics, our company envisions a global shift towards healthier fats, redefining the role of oleogels and bringing their benefits to society.

In this article, the reader can get a glimpse of the journey we have embarked on, gaining insight into the progress and cutting-edge research we are carrying out. Our pioneering spirit drives us to be the force initiating a new era for fats. We are creating a healthier and more sustainable future by igniting a revolution in the fat industry.