El Bulli – Spherification History
Frozen Reverse Spherification
10 Tips to Create a Perfect Sphere
7 Tips for Making Spherification Caviar
Getting Started with Spherification
The spherification technique was introduced by el Bulli in 2003. It consists of a controlled jellification of a liquid which forms spheres when submerged in a bath. The spheres can be made of different sizes and have been given names like caviar, eggs, gnocchi and ravioli. The resulting spheres have a thin membrane and are filled with the original liquid. A slight pressure of the mouth on the sphere makes them burst and release an amazing explosion of flavor. The spheres are flexible and can be carefully manipulated. It is possible to introduce solid elements in the sphere which will remain in suspension in the liquid giving the possibility of introducing multiple flavors and textures in one preparation. (see spherification recipes).
There are two main kinds of spherification techniques and each of them has its advantages and disadvantages which make them more suitable for certain recipes. The Basic Spherification technique consists of submerging a liquid with sodium alginate in a bath of calcium. The Reverse Spherification technique consists of submerging a liquid with a mixture of calcium gluconate and calcium lactate in a bath of sodium alginate. There are also a couple of other spherification techniques which consist of instant jelling by immersing the liquid in cold oil or liquid nitrogen.
The Basic Spherification technique is ideal for obtaining spheres with a very, very thin membrane that is almost imperceptible in your mouth. It results in a sphere that easily explodes in your mouth as if there is no solid substance between your palate and the liquid. The main problem of this technique is that once the sphere is removed from the calcium bath, the process of jellification continues even after rinsing the sphere with water. This means that the spheres need to be served immediately or they would convert into a compact gel ball with no magical liquid inside. The other issue of this technique is that jellification does not occur if the liquid acidity is high (PH<5) but this can be corrected by adding sodium citrate to the liquid to reduce the acidity level before the spherification process. Examples of Basic Spherification are "Spherical Mango Ravioli" and "Liquid Pea Ravioli" (shown below). Learn more about Basic Spherification.
The technique of Reverse Spherification is much more versatile than Basic Spherification as it can make spheres with almost any product. It is best for liquids with high calcium content or alcohol content. Contrary to the spheres made with the Basic Spherification process, these spheres have a thicker membrane and are long-lasting as the process of jellification can be stopped when the sphere is removed from the sodium alginate bath and rinsed with water. Thanks to these characteristics, the Reverse Spherification spheres can be manipulated more easily and can be used in more ways (for example as fillings in sponge cakes or mousses, in cocktails or can even be macerated in aromatized olive oil for a few days). Examples of Reverse Spherification are "Yoghurt Spheres", "Liquid Mozzarella Spheres" and "Spherical Olives" (shown below). Learn more about Reverse Spherification.