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Abstract The contribution of a hollow structure on the rheological behavior of granular suspensions remains un‐investigated due to the challenge of water impermeability. Here starch is used to fabricate water‐permeable hollow particles, as a model for granular suspensions and investigated the resulting microstructures and rheological behavior. The hollow structure is fabricated based on a bottom‐up method by assembling micron‐sized building blocks into a superstructure. A Pickering emulsion is heated to fuse the starch interface, then, upon antisolvent precipitation, the polymer strands interlock to form a rigid shell around the oil template. When the template is removed a hollow particle remained. These particles exhibited a specific volume >5‐times higher than unmodified starch and consequently a higher viscosity. Larger particles showed higher viscosity but are also more fragile. The template structure can be manipulated to fine‐tune their functionality. These micro‐sized building blocks made from edible materials can be used as the next generation of texturizers. Additionally, these water‐permeable colloidosomes present an innovative approach to understanding how micro‐architectures impact the rheological behavior of granular suspensions. 

The idea of building large structures from small building blocks has had a long history in the human imagination, from the beautifully intricate shells assembled from silica by unicellular algae to the Egyptian pyramids built from stone. Carrying this idea into the food industry has important implications. Here, we introduce a Pickering emulsion platform for building superstructures like hollow cages and sheets using starch granules as building blocks. In food, these superstructures occupy up to six times more space than their constituent parts, thereby delivering a viscosity greater by an order of magnitude than unstructured starch. To achieve this higher viscosity, they use an alternative superstructure mechanism as opposed to the classic swelling mechanism of individual particles. These super-thickeners may reduce calories, cut production costs, and stretch the global food supply, demonstrating how we can design the future by playing with our food.