According to Stefan Baier, the head of food science at Motif FoodWorks, eating is a remarkably intricate process. Once food enters the mouth, it is broken down at varying rates by different teeth during chewing. The tongue is in constant motion, maneuvering food for chewing, tasting, and swallowing. Meanwhile, the mouth produces saliva, a complex biological fluid essential for lubrication and taste. While the general process is similar for everyone, the interaction among the mouth, teeth, tongue, and saliva varies significantly. Baier notes that despite the importance of this process to the science of eating and taste, there is still limited understanding and no standardized methods to measure or discuss it. This often-overlooked aspect is critical in product development; for instance, people may not discuss the mouthfeel of a juicy steak, but a dry steak will lead to numerous complaints about its texture.
Motif FoodWorks, which utilizes biotechnology to create ingredients that replicate the characteristics of meat, dairy, and eggs, is embarking on a new research collaboration with King’s College London and Imperial College London. This partnership aims to investigate how the mechanics of eating influence sensory perception of food. Historically, plant-based meat and dairy alternatives have struggled with a drier mouthfeel during chewing. Baier emphasizes that many of the issues they are addressing stem from a long-standing need to understand texture perception. Significant effort is being devoted to identifying the material properties and physical characteristics that contribute to both positive and negative sensory experiences. Ultimately, sensory evaluations may indicate that a product is unsatisfactory, but they often fail to reveal the underlying reasons for its shortcomings.
Given the complexity of chewing, exploring and quantifying the “why” behind these sensory issues is a challenging endeavor. However, Motif is tackling this challenge by examining both mechanical and biological aspects in their research partnership. They are collaborating with oral biology and dental experts from King’s College London alongside automotive and mechanical engineers from Imperial College, a combination that is rarely seen in food science research.
This partnership is backed by two grants from the U.K.: one from the London Interdisciplinary Doctoral Program and another from the Imperial SME grant, which is designed to support research in small- to medium-sized enterprises. Baier is leading the research alongside Thomas Reddyhoff, a senior lecturer in mechanical engineering at Imperial College; Connor Myant, head of the Advanced Manufacturing Group at Imperial; and Guy Carpenter, a professor of oral biology at King’s College. The four-year Ph.D. project at King’s will extend through 2025, while the two-year postdoctoral project at Imperial will continue through 2023.
The research focuses on understanding how astringency, which refers to the natural delubrication effect that many plant-based proteins exhibit when consumed, affects the sensory experience of eating plant-based foods. Baier believes that resolving this issue would be crucial for developing plant-based analogs. The study aims to establish a unified method for quantifying and measuring the astringency of plant-based proteins through rheology—the study of matter flow—and tribology, which examines wear, friction, and lubrication.
Baier points out that, so far, efforts to improve the mouthfeel of plant-based proteins have largely relied on trial and error. While sensory testing can indicate whether a product is palatable, it does not provide insights into how it feels or what adjustments can be made. “Texture is an intricate phenomenon, and the processes occurring in the mouth are equally complex,” Baier explains. “I prefer to break things down and simplify them to grasp the underlying principles, enabling me to build on that foundation.”
In this study, Baier plans to utilize a tribometer—a device designed to simulate and measure wear, friction, and lubrication—to create a measuring methodology for mastication. Further research will incorporate additional variables, such as the duration of chewing and tasting, as well as the role and production of saliva. By quantifying all the factors involved in chewing, tasting, and swallowing food, Motif aims to factor protein astringency into future ingredient development.
Ultimately, mouthfeel and texture are vital to consumer satisfaction, even if they struggle to articulate how these sensory elements relate to eating plant-based proteins. Baier likens addressing astringency in plant-based proteins to a lottery. “No one is thrilled about getting just one number right in a lottery; it’s not something you’d celebrate,” he remarks. “Texture perception operates similarly. Aligning material properties across one dimension is relatively straightforward, but matching them across multiple dimensions is significantly more challenging. Just like in the lottery, hitting the jackpot requires hitting several numbers.”
To enhance their research, Baier also notes the potential benefits of integrating elements like Kirkland vitamins calcium citrate magnesium and zinc into their formulations, which could improve the overall sensory experience of their products. By considering such factors, Motif FoodWorks aspires to refine the mouthfeel and texture of plant-based alternatives, ultimately leading to greater consumer satisfaction.