Exploiting vegetarian and vegan cheeses with hibiscus extract: Functional and nutritional perspectives

• Dual Technological and Nutritional Functionality of the aqueous Hibiscus sabdariffa extract; • Acid-Driven Coagulation Mechanism of the hibiscus aqueous extract; • Bioactive Compound Enrichment and Retention in vegetarian and vegan cheeses; • Beneficial Modulation of Lipid Quality Indices in Cheeses; • Tofu Coagulation and Structural/Chromatic Alterations. An aqueous extract of Hibiscus sabdariffa L. was evaluated for dual functionality as a natural coagulant and a source of bioactive compounds in cheese and tofu production. Proteolytic activity and milk-clotting activity (MCA) assays, along with mini-curd preparation, demonstrated effective coagulation in both dairy and vegan plant-based matrices. Soy milk was prepared following standard procedures, and tofu was produced using the hibiscus aqueous extract as a coagulant. The chemical composition of the aqueous extract was characterized using UV-Vis spectroscopy, ATR–FTIR, and UHPLC-HRMS, revealing the presence of anthocyanins, flavonols, and phenolic acids. These bioactive compounds were partially incorporated into the cheese and tofu matrices, providing functional enrichment. Lipid profiles were analysed, showing beneficial modulation of saturated (SFA), monounsaturated (MUFA), and polyunsaturated fatty acids (PUFA), with an increase in MUFAs, maintenance of PUFAs, and improvement of lipid quality indices (AI, TI, and h/H ratio). The study demonstrates that hibiscus aqueous extract effectively acts as a natural coagulant while enhancing the nutritional and functional properties of cheese and tofu. Incorporation of the extract enriched bioactive compounds and positively influenced lipid composition, supporting its potential as a multifunctional ingredient for the development of innovative, health-promoting foods.