Spherification is the culinary process of shaping a liquid into spheres which visually and with a texture resembling caviar.
There are two main methods for creating such spheres, which differ based on the calcium content of the liquid product which needs to be made into spheres.

For flavored liquids (such as fruit juices) containing no calcium, the liquid is thoroughly mixed with a small quantity of powdered sodium alginate, then dripped into a bowl filled with a cold solution of calcium chloride or calcium carbonate, depending what the recipe calls for.

Just as a teaspoonful of water dropped into a bowl of vegetable oil forms a little bubble of water in the oil, each drop of the alginated liquid forms into a small sphere in the cold calcium solution. During a reaction time of a few seconds to a few minutes, the calcium solution causes the outer layer of each alginated liquid sphere to form a thin, flexible skin. The resulting artificial “caviar” balls are removed from the calcium-containing liquid bath, rinsed in a bowl of ordinary water, removed from the water and saved for later use in food or beverages.

To the similar process there is also a reverse spherification, for use with substances which contain calcium or have high acid or alcohol content, it requires dripping the substance into a solution made from sodium alginate.

A cheats way of doing so is also chilling the oil overnight in the refrigerator. The liquid which need to form spheres is boiled with some agar-agar until is dissolved. Then the mixture is cooled down and put in a syringe and dropped in a the chilled oil in form of drops. Then the mixture is strained and washed in running cold water and used as required.