Meat analogs: Protein restructuring during thermomechanical processing

Increasing awareness of inefficient meat production and its future impact on global food security has led the food industry to look for a sustainable approach. Meat products have superior sensorial perception, because of their molecular composition and fibrous structure. Current understanding in the science of food structuring has enabled the utilization of alternative or nonmeat protein ingredients to create novel structured matrices that could resemble the textural functionality of real meat. The physicochemical and structural changes that occur in concentrated protein systems during thermomechanical processing lead to the creation of a fibrous or layered meat-like texture. Phase transitions in concentrated protein systems during protein-protein, protein-polysaccharide, protein-lipid, and protein-water interactions significantly influence the texture and the overall sensory quality of meat analogs. This review summarizes the roles of raw materials (moisture, protein type and concentration, lipids, polysaccharides, and air) and processing parameters (temperature, pH, and shear) in modulating the behavior of the protein phase during the restructuring process (structure-function-process relationship). The big challenge for the food industry is to manufacture concept-based (such as beef-like, chicken-like, etc.) meat analogs with controlled structural attributes. This information will be useful in developing superior meat analogs that fulfill consumer expectations when replacing meat in their diet.