Structuring processes for meat analogues

Animal-derived protein foods, such as meat, have a large impact on the environment. Meat analogues are products that replace meat in its functionality, i.e. have similar product properties and sensory attributes, which is achieved by the fibrous nature of those products. The techniques used to make fibrous products that mimic muscle meats are outlined and categorized based on their approach. The bottom-up approach refers to assembly of structural elements that are combined. The top-down approach refers to structuring of biopolymer blends using an overall force field. The strengths and weaknesses of these approaches are discussed in terms of ingredient and equipment use, (achievable) product resemblance, robustness, scalability, and resource efficiency. To enlarge the theoretical framework, the techniques with the top-down strategy are further contextualized by relating to structure formation processes of materials with other applications, and the methods to analyse the fibrous structures are further outlined. Techniques that follow the bottom-up strategy have the potential to resemble the structure of meat most closely, by structuring the proteins hierarchically through assembly of individual structural components. The top-down strategy is better scalable, is more efficient in its use of resources, but can only create the desired structure on larger length scales. Significant progress has been made on the methods to analyse structured products from the last category. Most analysis methods focussed on the (micro)structural anisotropy of the fibrous products, however there is also a need for methods that allow in situ analysis of the evolution of the structure during processing.