Kansui

Sources of alkali

High alkalinity is typically achieved by the introduction of sodium carbonate (Na₂CO₃ or sodium salt of carbonic acid) into the primary ingredients. In parts of China in which alkaline wheat noodles are common, they are traditionally made with alkaline water from wells. More commonly a mixture of 20% sodium carbonate, which is also an anti-caking agent, and 80% potassium carbonate in water is added directly. This mixture is what the Chinese call jian (碱) or jian shui (碱水) and what the Japanese call kansui (かん水). Sometimes kansui can also be a solution of sodium hydroxide or a powdered mix of sodium carbonate, potassium carbonate, and sometimes sodium phosphates in various proportions (solid kansui).