Influence of four different coagulants on the physicochemical properties, textural characteristics and flavour of tofu

The coagulation mechanism and quality characteristics of tofu depend on the choice of coagulant. The effects of using magnesium chloride (MgCl2), calcium sulphate (CaSO4), glucono-delta-lactone (GDL) and fermented soybean whey (FSW) as coagulants for tofu were investigated using solid-phase microextraction (SPME), two-dimensional gas chromatography coupled with mass spectrometry (GCxGC-MS), scanning electron microscopy (SEM) and analysis of textural characteristics and physicochemical properties. Results showed that GDL tofu exhibited the highest yield (202 g 100 g(-1)) and moisture content (76.3%). FSW tofu had the highest protein content (18.5%), amino acid content (15.85%) and textural properties. GCxGC-MS analysis revealed the number of 49, 44, 55 and 63 flavour substances, respectively. In sensory evaluation tests, GDL tofu was reported to possess a smooth surface and white colour. The microstructure of FSW tofu was dense and uniform. Through the above technical researches, the study suggested FSW gave tofu the best quality, more unique flavour and more potential popular among consumers.