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Updated: May 11, 2026

Calcium Carbonate Formation in the Presence of Biopolymeric Additives
Published on: May 14, 2019
Magnesium chloride concentration-dependent formation of tofu-like precipitates with different physicochemical
Yasuhiro Arii1, Yasuyuki Takenaka
1Department of Dietary Life and Food Sciences, Junior College Division, Mukogawa Women's University, Nishinomiya, Hyogo, Japan. arii@mukogawa-u.ac.jp
Abstract:
A wet precipitate is generated in the process of making tofu by adding a coagulant to the basic soymilk ingredient. We investigated the magnesium chloride concentration-dependent change in the precipitate weight. The wet precipitate weight dramatically increased following a short plateau phase at a low concentration of magnesium chloride. It is interesting that this weight slightly decreased following a long plateau phase at a high concentration. These low and high concentrations respectively induced precipitates with a smooth surface and rough surface. The precipitate with a smooth surface had a higher water content than that with a rough surface. These precipitates also had obviously different solubility in various chemical reagents. The different properties indicate that these precipitates were formed by different intermolecular interactions. These results can be utilized to more clearly understand the mechanisms involved in tofu formation.
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