Plant-Derived Extracts in Tofu Production and Functionalization: Current Status and Future Perspectives

Tofu is a traditional staple food widely consumed in Asian countries, that is currently experienced rapid growth and consumer demand across other continents. Conventional tofu production relies on the coagulation of soy proteins using established mineral salts or organic acids. In recent years, research has increasingly focused on exploring plant-based coagulants as natural alternatives to align with clean-label trends. Various plant extracts rich in proteolytic enzymes, organic acids, and other bioactive compounds, such as those derived from lime, Tamarindus, Hibiscus, Calotropis, Moringa, ginger, Phyllanthus, and Passiflora, have been investigated for their efficacy in inducing soymilk coagulation, alongside their effects on product yield, structural properties, and sensory attributes. In parallel, the incorporation of functional plant extracts, either during or post-coagulation, represents an innovative strategy to enhance the nutritional profile of tofu. Extracts rich in polyphenols, flavonoids, and antioxidants can confer valuable health-promoting properties; however, these additions may concurrently modify colour, flavour, texture and shelf-life of the final product, thereby requiring careful formulation optimization. The combined use of plant-based coagulants and functional plant-derived ingredients constitutes a promising avenue for developing next-generation soy-based products. This review provides a comprehensive overview of the current state of the art concerning the application of plant extracts in tofu manufacturing, highlighting technological challenges, product modifications, and future research perspectives.