Healthy and sustainable food made in Fribourg

Imagine foods rich in nutrients and able to provide a long-lasting feeling of fullness. That is the dream of anyone who has ever had to follow a strict diet. The team headed by Professor Stefan Salentinig of the Chemistry Department at the University of Fribourg is on the verge of making that dream a reality. By combining and optimizing the benefits of whey and buriti oil, the team is developing, through innovative analyses, a promising new class of healthy functional food materials. Their work has been published in the journal Advanced Functional Materials.

Lactoserum, or whey, is a well-known product since it is an ingredient in a typically Swiss drink, Rivella. It is the pale yellow liquid that remains in the vat once the curd is fully formed in the process of making cheese. Whey proteins are a source of high-quality nutrients that are easy to digest and high in amino acids. In this study, they are used to create oil emulsions in water.
Buriti oil is a unique source of nutrients. A team of University of Fribourg scientists working with the Swiss Nutrition and Health Foundation (SNHf) demonstrated this with a chemical and structural analysis. Extracted from the Amazonian superfruit buriti, sourced from a species of palm (Mauritia flexuosa) that grows in tropical South America, buriti oil is naturally rich in carotenoids, vitamins E and C, phenolic compounds, and unsaturated fatty acids. “These exceptional properties make buriti oil an ideal ingredient when developing innovative foods. Not to mention that its unique concentration of antioxidants gives it a long product shelf life, along with the potential health advantages,” Rafael Freire, a PhD student who took part in the study, explained. By emulsifying buriti oil with whey proteins, the UniFri scientists created a new ingredient that could eventually be used in manufacturing food products and drinks. The natural structures they discovered allowed the team to generate functional food properties that make nutrients more readily available for uptake into the body during digestion by keeping them in solution.

High-tech cooking
This groundbreaking research is based on an in-vitro human digestion model developed specifically for this project. The model simulates the oral, gastric, and intestinal stages of digestion. By drawing on leading-edge technologies, like small-angle X-ray scattering (SAXS), cryogenic electronic microscopy (cryo-EM), and light scattering, the researchers could observe the changes occurring in the food bolus during digestion in real time. The professor of physical chemistry and director of the project Stefan Salentinig explained, “Using optimized emulsification techniques and tailoring composition, we optimized the structure of the foods, from the molecular to the microscopic scale. In this way, we were able to obtain targeted properties and, therefore, specific effects, for example, helping individuals on a diet to feel full for longer, which makes their treatment more tolerable, or improving the availability and potential absorption of nutrients, one could even think of adapting them to the personal condition of an individual.”

A sustainable nutraceutical
Beyond its scientific and nutritional importance, this research offers two major advantages. First, it promotes a more circular economy by expanding the market for whey, a sidestream product of the dairy industry, combined with plant oil, into high-value food materials. Secondly, harvesting the buriti fruit is of immense socio-economic value for the local populations of the Amazonian region because it offers the possibility of creating livelihoods for them.

Fribourg, a canton for innovative food research
This study also highlights the benefits of interdisciplinary research. Such an approach combines fundamental and applied aspects of physics, chemistry, materials engineering, nutrition, and biology. Professor Salentinig is looking forward to continuing to work along these lines, “The future Food Research and Innovation Center (FRIC) of the University of Fribourg will become an interdisciplinary research hub, encouraging this union of science, innovation, and application for sustainable food.” FRIC will be opening its doors in the coming year.

Read the article Structure Formation in Tailor-Made Buriti Oil Emulsion During Simulated Digestion