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Ruud van der Sman uses physics to create healthier and more sustainable food
As special professor of Modelling of Food Materials Engineering, Ruud van der Sman explores how we can make food healthier and more sustainable by understanding its microscopic structures. After being postponed twice, he delivered his inaugural lecture on Friday, 13 December. In it, he emphasises the added value of a physics-based approach in food science. "Its complexity might scare off some food scientists, but I find it fascinating."
To boldly go where no foodie has gone before – that is the title of the inaugural speech by Ruud van der Sman (Food Process Engineering chair group). With this nod to Star Trek, he refers to the adventure of exploring the relatively uncharted territory between food science and physics. With his background in physics, Van der Sman sees food science as a "goldmine", full of open questions. While food might appear simple, its structures on a microscopic scale are shaped by physics and chemistry. Those structures determine taste and texture. Fellow researchers record such microstructures experimentally, after which Van der Sman uses computational calculations to uncover how these microstructures form.
Less sugar
One of Van der Sman’s missions is to make food healthier by reducing its sugar content. However, sugar influences not only taste but also texture and mouthfeel. “Traditionally, food scientists replace ingredients one by one and analyse the effect on the final product,” he explains. Van der Sman opts for a more systematic approach by studying food at the molecular level. At that scale, sugars form hydrogen bonds with water molecules. “The more of those hydrogen bonds, the more viscous the food,” Van der Sman explains. Sweeteners form similar bonds with water molecules, but to a different extent. "By calculating how much of each sweetener we need to match the amount of hydrogen bonds, we can replicate the texture of traditional bakery products," says Van der Sman.
As a physicist, I view food as a goldmine. There are so many open questions
Sugar also makes baked goods soft. Using the right amount of sugar and water creates the soft bite of cake, or gives cookies their crunch. The art of baking is finding the right balance in this. Replacing sugar with sweeteners disrupts this delicate balance. The solution? Mix sugar substitutes of different sizes to mimic sugar’s average ‘behaviour’. It works. A test panel was given cookies and cakes with less sugar, made with proportions as calculated by Van der Sman and his team. Based on mouthfeel and texture, the test subjects could not distinguish these low-sugar versions from traditional pastries. Ergo, physics makes it possible to design healthier products without compromising on sensory experience.
Towards sustainable solutions
Van der Sman’s research goes beyond creating healthier baked goods. His methods also contribute to sustainability. "By combining physics-based simulations with extensive data from food science, we combine the power of physics and efficiency," he says. This enables, for example, calculations of the ripeness and quality of fruits like avocados, thereby reducing food waste. His team has also studied the molecular forces in meat to understand juiciness. "We can use that knowledge to give meat substitutes a similar juiciness," says Van der Sman.
When disciplines work together, we can make a real impact on the consumer's plate
As a pioneer of physics in food processing, Van der Sman aims to bridge the gap between theory and practice in the field of nutrition. "My goal is to transfer fundamental knowledge from academia to industry and inspire physicists to contribute to food science." The special professor wants to stimulate collaborations between disciplines. "By working together, we can truly transform what ends up on the consumer’s plate."
About Ruud van der Sman
Ruud van der Sman studied Applied Physics at TU Delft and began his career as a lecturer at Utrecht University of Applied Sciences. In 1999, he earned a PhD from ATO-DLO (now WFBR, part of Wageningen University & Research) for research on heat and mass transfer in packaged roses and potatoes. He then split his time between a position as assistant professor in Food Process Engineering at Wageningen University and his research at WFBR. Here he performs mesoscopic simulations of complex fluid flows in food processing, such as emulsification and filtration of suspensions. In addition, he developed expertise in the physics of edible soft matter. As a senior researcher at WFBR, Van der Sman applies his expertise in the physics of soft edible matter to develop practical solutions for healthy, sustainable food in collaboration with industry. In 2019, he was appointed professor by special appointment in Modelling of Food Materials Engineering. After pandemic-related delays, his inaugural lecture took place on 13 December 2024.