Gluten, a large natural protein, possesses remarkable properties in maintaining the airiness of dough until baking, resulting in a stabilized open-pore structure. Prof. Dr. Mario Jekle, based at the University of Hohenheim in Stuttgart, is dedicated to developing processes where specific proteins sourced from peas, rapeseed, rice, maize, and other ingredients can directly substitute gluten protein or be combined to form chains with gluten-like characteristics. Saponins from daisies and quinoa seeds, as well as mucilages from cereal hulls, further enhance the formation of light and airy dough while providing valuable dietary fiber. The outcome of these advancements can be readily baked in traditional ovens or even 3D printed, offering energy-efficient production methods with additional creative possibilities.
At the Technical Center for Food Science, the current output of rolls is still modest. Natalie Feller, a doctoral candidate from the University of Hohenheim’s Department of Plant-Based Foods, carefully portions 30-gram dough portions into small silicone box molds, resulting in rolls roughly the size of a model train car.
The miniature rolls undergo a steaming process, surrounded by moisture for a distance of over two meters. This is followed by an additional two meters in the continuous baking oven. At the conclusion of the miniature baking line, the test loaves emerge, appearing light, golden, and steaming.
Feller’s objective for the day is to achieve the utmost fluffiness in the bread. To pursue this, she has transitioned from the laboratory to the Technical Center, which provides food scientists at the University of Hohenheim with a comprehensive range of equipment resembling those used in bakery trades, dairies, and butcher shops.
Gluten proves to be a problematic protein in about 2% to 3% of the population
Feller’s baking experiment brings together various disciplines, including food technology, materials science, and engineering. The unique challenge lies in creating a recipe that is entirely gluten-free yet still yields fluffy and delicious baked goods.
This endeavor is motivated by the fact that gluten poses issues for approximately 2% to 3% of the population. “We now recognize three disease patterns associated with gluten,” explained Prof. Dr. med. Stephan Bischoff from the Institute of Clinical Nutrition at the University of Hohenheim.
The most well-known condition is celiac disease, which combines elements of an allergy and an autoimmune disorder. Bischoff highlighted that wheat allergy, triggered by gluten and similar peptides, is also prevalent. Additionally, there is a third clinical presentation known as wheat sensitivity, which remains relatively understudied. “It is not yet fully understood what causes wheat sensitivity and whether gluten plays a role in this particular case. At our department, we are diligently working to unravel this puzzle.”
Individuals with celiac disease, in particular, have only one solution in their everyday lives: to rely on gluten-free foods.
In classic baked goods, gluten serves as a supporting framework
From a chemical and physical perspective, gluten holds significant importance, according to Prof. Dr. Mario Jekle, the head of the Department of Plant-Based Foods. “Gluten stands out not only as one of the largest proteins known in the world but also for its exceptional properties in baking,” highlighted the food scientist.
To envision it, a fully proofed dough can be likened to a foam that solidifies during the baking process. The protein gluten provides structure to this foam, ensuring its stability and preventing premature collapse.
This crucial aspect is often absent in many gluten-free baked goods. “Creating the airiness in the ingredients is not the challenge. This can be achieved through stirring or by employing leavening agents such as yeast or baking powder, just like in traditional wheat flour dough,” explained Jekle. “What has proven incredibly difficult thus far is maintaining the multitude of small gas bubbles within the dough without the supportive gluten framework.”
Protein chains from natural proteins may provide a solution
The food researchers at the University of Hohenheim are taking a fresh approach in their current research. Instead of relying on gluten to support the dough, they are focusing on stabilizing the interface between gas bubbles and the dough using alternative proteins, as explained by Prof. Dr. Jekle.
To achieve this, the scientists are utilizing custom-designed proteins. They start with natural proteins derived from peas or rapeseed and extract the most suitable proteins for their purposes.
These novel protein alternatives are complemented by natural saponins. These saponins are sourced from quinoa seeds or even from the stems, leaves, and flowers of daisies.
Prof. Dr. Jekle also recognizes the potential of plant breeding in this context. By precisely defining the requirements, they can collaborate with plant breeders to develop new varieties of peas with proteins that are even better suited for their innovative approach.
Second approach provides additional dietary fiber
The Department of Plant-Based Foods at the University of Hohenheim is exploring another innovative approach, which involves linking natural proteins from rice, maize, or oats with mucins known as arabinoxylans. These mucilages are abundantly present in cereal hulls, commonly used as bran or animal feed.
This approach offers additional advantages as it allows Prof. Dr. Jekle’s team to incorporate valuable dietary fiber into baked goods. The significance of dietary fiber is underscored by clinical nutritionist Prof. Dr. Bischoff from the University of Hohenheim, who highlights its role in preventing colon cancer—one of the most prevalent cancers in both men and women. Consuming thirty grams of fiber per day is considered a beneficial preventive measure.
Furthermore, the food scientists at the University of Hohenheim are planning to explore the utilization of arabinoxylans in other food products, such as meat substitutes. What makes this approach particularly exciting is that it not only enables the creation of substitute products with a meat-like texture but also provides the unique additional benefit of dietary fiber. Currently, there are no comparable products available in the market, making this research highly innovative and promising.
In the near future, bread could also come from the 3D printer
Another exciting vision is the integration of dough loosening and baking processes into a single step using 3D printers. In this innovative approach, a nozzle deposits the dough in thin layers, simultaneously creating the desired porous structure. Above the dough, a baking unit promptly solidifies each layer, resulting in the formation of the final product.
This concept shares similarities with the traditional baking technique employed by Salzwedel bakers for the renowned Baumkuchen cake, where layers of dough are meticulously applied and cooked over an open fire. However, the technology developed at the University of Hohenheim offers much greater sophistication, flexibility, and the ability to construct diverse structures, according to Prof. Dr. Jekle.
For Prof. Dr. Jekle, the 3D printer has become an essential tool, and he has been conducting experiments with it for several years. Whether it is baked goods, meat, meat substitutes, or side dishes, he believes that virtually any food could be produced using a 3D printer, assembling individual components into a final product.
In addition to its versatility, the 3D food printer offers two significant advantages over traditional cooking methods. First, it allows for personalized meals, enabling precise customization of the ratio of fats, carbohydrates, proteins, and other components to suit individual dietary needs. Second, the printer can utilize by-products generated during food production, contributing to the sustainable utilization of residual materials.
Overall, the integration of 3D printing technology into the culinary world opens up new possibilities for personalized and sustainable food production, revolutionizing the way we prepare and consume meals.
Source: University of Hohenheim