In Europe 53% of the population is overweight or obese. Obesity caused an estimated 4.0 million deaths in 2015, along with 120 million people living with disabilities. Several factors promote obesity and related health conditions in individuals, but excessive dietary caloric intake is the predominant cause. Edible lipids (such as fats and oils) are the most energy-dense macronutrient and their overconsumption, together with that of sugar, determines excessive dietary caloric intake. Dietary guidelines issued by the European Food Safety Authority (EFSA) recommend that fats constitute 20–35% of the total dairy energy intake, and that the amount of saturated fatty acids is limited to 10% in such intake. However, data shows that only 5 European countries meet this recommendation. For this reason, food researchers and technologists have recently focused on formulating novel food products with reduced amounts of fats, particularly saturated ones. Nevertheless, fats are still an essential macronutrient, with the ability to solubilize and enhance the uptake of specific micronutrients (e.g. vitamin D, E and tocopherols). Additionally solid fats provide desirable texture and palatability to food products, making their reduction or replacement extremely challenging.
Oleogels & oleocolloids might be a possible replacement for pure fats. Oleogels are materials with reduced content of saturated fatty acids, achieved via the structuring of a liquid oil with a gelator agent (e.g. waxes, saturated lipid molecules). Due to their gel-like consistency, and the presence of solid crystals that can act as Pickering stabilizer, oleogels can be used as precursors for the formulation of more complex low calorie food structures, such as oleofoams or emulsions, which are normally called oleocolloids. Oleogels and their derived structures are also promising pharmaceutical formulations. In fact, thanks to their soft texture, oleogels & oleocolloids are easier to administer than solid tablets to pediatric patients or those suffering from dysphagia (e.g. older population). Additionally, via modulation of their microstructure, oleocolloids can allow precise, controlled release of active pharmaceutical ingredients.
The application of oleogels is still limited due to several regulatory, technological and environmental limitations. We propose to overcome this issue by the development of a sustainable process for the production of self-structuring oleogels, starting solely from liquid oils with low.
The technology developed in NewOilFactory focuses on crystalline oleogels, which are a particular class of oleogels that require mild processing conditions (e.g. lower temperatures), and whose functional properties can be tailored via accurate control over the crystallization process. The mechanism of stabilization in crystalline oleogels is the formation of a network of crystals that restricts the movement of the liquid oil, imparting solid-like properties to the resulting material. In NewOilFactory we developed and validated at laboratory scale a process for the production of crystalline, self-structuring oleogels made solely from sustainable liquid oils, without using hydrogenated fatty acids or expensive gelling agents. Our process is designed to enable further modulation of the oleogel structure to achieve a fine-tuning of its properties (e.g. melting point, rheological behavior and digestibility).
The number of publications and patents related to oleogels has considerably increased in the past 10 years, with almost 50 patents granted only in 2022. This proves the interest in these types of materials in food, cosmetic or pharmaceutical formulations. Nevertheless, there are still very few commercialized oleogels, either as ingredients or final products (e.g. cosmetic oleogels from different producers). This is mostly due to limitations intrinsically related to the types of gelators currently used to formulate oleogels. In fact, common gelators are:
• Made of hydrogenated fatty acids. It is well known that hydrogenation of liquid oils can cause the formation of trans-fats, which are now strictly regulated by the EU due to health concerns.
• Synthetic or semi-synthetic (e.g monoglycerides, polyglycerol polyricinoleate); hence not positively perceived by consumers, who prefer “clean-labelled”, natural products.
• Natural extracts that are produced via high energy and low sustainability processes such as γ-oryzanol and β-sitosterol or complex materials such as beeswax or rice wax.
• Self-assembling hydrocolloids (6,9) that require high temperatures (>100°C) and/or other high energy unit operations (e.g. drying) to deliver oleogels.
• Solid fats of animal origin (e.g. tallow, milk), or from tropical sources (e.g. cocoa butter, palm, coconut). These TAGs mixtures are not sustainable (e.g. palm fat) or are expensive commodities, such as cocoa butter.
The NewOilFactory approach overcomes these limitations by:
1) the development of an innovative process for self-structuring oleogels, which can achieve a gel-like consistency without hydrogenation or the addition of expensive gelators (e.g. beeswax);
2) the use of optimized sequences of low energy unit operations such as enzymatic interesterification and fractionation, specifically designed to deliver self-structuring oleogels with tailored functionality, with reduced manufacturing costs and waste of time & resources;
3) the use of sustainable liquid oils, with the aim of reducing the environmental impact of oleogel production.
