קרישים נפוצים המשמשים בייצור טופו תעשייתי
In tofu manufacturing, the choice of coagulant directly determines protein coagulation behavior, texture, water retention, and final product stability.
Industrial tofu production commonly uses four types of coagulants: calcium sulfate, magnesium chloride, glucono delta-lactone (GDL), and fermented whey. Each has distinct functional characteristics and application scenarios.
Calcium Sulfate (Gypsum, CaSO₄)
Calcium sulfate is one of the most widely used coagulants in tofu production. In industrial applications, cooked gypsum (CaSO₄·H₂O) is preferred due to its controllable reaction speed and stable performance.
Calcium sulfate has low solubility, resulting in a slow and uniform coagulation process. This produces tofu with high water retention, a smooth surface, and a delicate internal structure. Because of its gentle reaction, it is especially suitable for soft tofu products that require good appearance and consistency.
Magnesium Chloride (Brine, MgCl₂)
Magnesium chloride-based brine coagulates soy protein quickly and strongly. Compared with calcium sulfate, it forms a tighter protein network, which tends to contract during coagulation, leading to lower water retention and a firmer texture.
Due to these characteristics, magnesium chloride is commonly used for firm tofu, pressed tofu, and dried tofu products. In industrial production, refined solid magnesium chloride is recommended to avoid bitterness and improve product consistency. Typical usage ranges from 2–5 kg per 100 kg of soybeans, depending on product requirements.
Glucono Delta-Lactone (GDL)
GDL is a heat-activated acid coagulant widely used in silken and packaged tofu production. When dissolved in soy milk, GDL slowly hydrolyzes into gluconic acid. Protein coagulation begins at approximately 60°C, with optimal gel formation occurring at 80–90°C.
This gradual acidification creates a fine, elastic protein gel with excellent water-holding capacity, resulting in tofu with a smooth, uniform, and silky texture. GDL is typically added at 0.25–0.30% of soy milk weight. In some formulations, small amounts of food-grade phosphates are used to further improve flavor and gel stability.
Fermented Whey (Acid Whey)
Fermented whey is a traditional coagulant produced by microbial fermentation of soybean whey. It contains organic acids, whey proteins, beneficial microorganisms, and enzymes that contribute to natural coagulation.
Compared with chemical coagulants, fermented whey produces tofu with a distinct traditional flavor and softer structure, but its coagulation behavior is more variable. In modern production, controlled fermentation systems are increasingly used to stabilize acidity and improve batch-to-batch consistency.
Choosing the Right Coagulant for Tofu Production
In industrial tofu manufacturing, no single coagulant is universally “best.” The correct choice depends on the target product:
- Calcium sulfate for smooth, high-moisture tofu
- Magnesium chloride for firm, low-moisture tofu
- GDL for silken and packaged tofu
- Fermented whey for traditional or artisanal tofu
Understanding these differences helps manufacturers optimize product quality, processing stability, and equipment configuration.
