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Calcium Chloride

What is Calcium Chloride?

Calcium chloride, also known as CaCl₂ is a compound of chlorine and calcium that is a byproduct of sodium bicarbonate (baking soda) manufacturing. At room temperature it is a solid salt, which is easily dissolved in water.

This is very salty and is often used for preservation, pickling, cheese production and adding taste without increasing the amount of sodium. It is also used in molecular gastronomy in the spherification technique for the production of ravioli, spheres, pearls and caviar.

When used for Spherification it is used together with sodium alginate due to the chemical reaction produced between these ingredients. Calcium chloride is dissolved in water for this process.

As an exothermic compound it can raise the temperature of the water up to 60ºC or 140ºF when dissolved. Calcium and chloride ions are transformed when exposed to water. The calcium then forms a polymer when it comes into contact with alginate.

A 0.5% calcium chloride bath is used for normal spherification, although the concentration may change according to desired effects. Some manufacturers also recommend using 1 liter of water with 6.5 grams of CaCl₂. Higher dosage will result in faster setting of the liquid in the bath. The longer the sodium alginate solution stays in the calcium chloride bath, the thicker the membrane becomes as well.