• Yakubu Ndatsu IBB University, Lapai
  • O.A. ALIYU
  • P.S. YISA
  • B.H. USMAN
  • B.H. USMAN




Natural coagulants, tofu, coagulation, Glycine max, Vigna subterranea


The effects of selected natural coagulants on the yield and quality Characteristics of Glycine max and Vigna subterranea Milk Mixture Tofu was investigated. The selected natural coagulants are Citrus lemon, roselle calyces (Hibiscus sabdariffa), Tamarindus indica, and influence water (steep water) from maize pap, while CaSO4 was used as a control group. The pH and titratable acidity values of the prepared tofu were performed. Tofu yield, proximate composition, and sensory quality of tofu prepared by natural coagulants of plant origins were also conducted and compared with that of CaSO4 coagulated tofu. Results showed that natural coagulants recorded lower values of pH (3.54-20.00) and increased values of percentage (%) acidity (0.12-1.20%) as compared to synthetic coagulant (21.03 and 0.09%), respectively. Likewise, lower levels of pH (6.77-37.45) and high values of percentage (%) acidity (0.18-0.35%) were observed in natural coagulated tofu than that of synthetic chemical coagulated tofu (40.42 and 0.12%), respectively. CICOT and STCOT recorded higher % of tofu yield (21.5% and 45.2%), proximate contents and panel overall acceptability (7.43% and 7.63%) as compared to others. In conclusion, citrus lemon extract and steep water coagulated tofu performed excellent in term of tofu yield with high quality and nutritional contents. Therefore, the consumption of tofu produced from natural coagulants, especially citrus lemon and steep water should be encouraged in the diets of vegetarians as source of protein.


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