Brining isn’t just for meat. When you soak dried beans in salted water, they cook up with softer skins. Why? It has to do with how the sodium ions in salt interact with the cells of the bean skins. As the beans soak, the sodium ions replace some of the calcium and magnesium ions in the skins. Because sodium ions are more weakly charged than calcium and magnesium ions, they allow more water to penetrate into the skins, leading to a softer texture. During soaking, the sodium ions will only filter partway into the beans, so their greatest effect is on the cells in the outermost part of the beans.
Brining Formula: For 1 pound of dried beans, dissolve 3 tablespoons of table salt in 4 quarts of cold water. Soak the beans at room temperature for 8 to 24 hours. Drain and rinse them well before using.
