Syneresis

The gradual leaking of liquid out of a gel, foam, purée, or sauce. This causes an unsightly rim of transparent liquid (mostly water) to encircle the sauce once on the plate. This effect is especially pronounced when a sauce gets its body from a large number of minute particles. Vegetable purée sauces and any sauce thickened with a purée are susceptible to syneresis. Many hydrocolloids and other thickeners and emulsifiers inhibit syneresis, allowing the particles in particle-thickened sauces to stay evenly distributed.