PhD defence by Guillermo Sedó Molina

Principal supervisor:

• Senior Scientist Claus Heiner Bang-Berthelsen

Co-supervisor:

• Professor Egon Bech Hansen,
• Associate Professor Lene Duedahl-Olesen

Examiners:

• Associate Professor Anurag Kumar Sinha, DTU Food
• Principal Research Scientist Vera Kuzina Poulsen, Novonesis A/S
• Independent Researcher Luc De Vuyst, formerly Professor at Vrije Universiteit Brussel (VUB), Belgium

Chairperson at defence:

• Assistant Professor Robin Dorau

Resume
The food industry is constantly seeking innovative and sustainable alternatives that benefit both consumers and the environment. In recent years, dairy and meat substitutes have gained popularity among those looking for more eco-friendly food choices. Replanted brings together expertise in food science, microbiology, and dairy alternatives to develop fermentation-based processes and microbial cultures capable of producing plant-based dairy alternatives that closely mimic traditional dairy products like yogurt and cheese. To achieve this, Replanted focuses on selecting and studying specific lactic acid bacteria (LAB) strains that can break down antinutrients and off-flavors in plant-based matrices, the two major challenges affecting consumer acceptance of these products.

During my thesis, we identified certain LAB species capable of degrading and removing these undesirable compounds when fermenting pea, oat, and potato protein blends. However, no single species was able to eliminate all antinutrients and off-flavors on its own. Instead, we found that a combination of multiple LAB species was necessary to achieve complete degradation, leading to the design of an optimized starter culture. Notably, plant-isolated strains such as Lactiplantibacillus plantarum, Leuconostoc mesenteroides, and Leuconostoc pseudomesenteroides demonstrated the ability to fully break down some unwanted compounds while partially degrading others. Identifying the best microbial candidates relies on understanding their genetic adaptation to their original environment, which influences their metabolic capabilities. Fermentation by microorganisms holds immense potential in the food industry, as microbes evolve and adapt genetically far more rapidly than animals. Understanding how specific microorganisms degrade undesirable compounds can extend beyond plant-based fermentation to applications such as food waste valorization, fermented animal feed, and alternative protein sources like insects and seaweed.

At Replanted, our goal is to improve both nutritional quality and taste through fermentation, building up the way for the next generation of sustainable and flavorful food products.

A copy of the PhD thesis is available for reading at the department.