Building a Structure with ProteinsIn summing up the challenges we are facing in food and agricultural production worldwide-change from fossil fuels to sustainable energy, climate change, food security and safety challenges, and population growth-it is clear that over the coming decades our ingenuity and creativity will be seriously tested. A growing population requires more food, and food proteins are well established as an important source of nutrition. The structures of muscles, connective tissues, organs, nails, and the brain are all based on proteins, making the importance of protein in our diet obvious.One challenge for the future is production of enough protein sources to feed the world, as well as to maintain a healthy balance between animal-and plant-derived proteins. Currently, in the more economically developed areas of the globe, such as North America and Europe, we rely strongly on animal-derived proteins. As these areas have developed over recent decades, animal-derived protein has become the larger portion of protein intake. For health and environmental reasons, it will be important to develop more diversity in industrial (alternative) proteins, protein products, and protein consumption. Although it is not a completely new area of food research (9), structuring, product development, texturizing, extrusion, and processing of alternative protein sources is a renewed area of interest. Many new protein pioneers in North America and Europe have stepped up to the challenge to help diversify the general diet with new protein-rich products. Whether it is the plant-derived meat burger, the plant-based steak (11), protein-enhanced cereal products, or cultured meat, it seems that a sense of urgency has created a new momentum in this field of food science and technology.During the manufacture of protein-based foods, proteins are hydrated, solubilized, or dispersed in water and then processed using mechanical and heat treatments to obtain a product with desired features. Choosing the right raw materials, ingredients, additives, and processing conditions are considered prerequisites for obtaining specific product properties. Product developers usually have to rely on their own experience when selecting the required ingredients and processing conditions for a product. Most of their knowledge stems from work with industrially produced animal-derived proteins such as dairy (casein, whey), egg (ovalbumin), and meat (myosin). When asked to "build a protein-rich food structure, " many of the aforementioned animal proteins may be at the top of the developer's ingredients list. In contrast to plant-derived proteins, there is a strong, established scientific base for how to use and process animal-derived proteins. Alternative proteins may not perform as expected under chosen conditions or might be "inferior" in their capacity to build the desired food structure (e.g., gelling, foaming, emulsion, meat patty, meat analog). The functional properties of alternative protein ingredients are not easy to predict-even generic rou...