Quillaja saponins are natural tensoactives (or surfactants) derived from the tree Quillaja saponaria, indigenous to Chile. They have been used for over 100 years as foaming agents in food and beverages, production of photographic films, adjuvants in animal vaccines, cosmetics, etc.

Quillaja saponins are non ionic surfactants, resistant to salt, heat, and extremely stable to acid pH. Chemically they consist of a triterpene, with sugar chains in carbons 3 and 28. Different sugar chains give rise to at least 50 different types of quillaja saponins. Molecular weight is of 1800 - 2000 Dalton. Below 200 - 500 ppm saponins exist as monomers; above 200 -500 ppm they aggregate as micelles, with a molecular weight of approximately 100.000 Dalton.

Figure 1: Chemical structure of quillaja saponins

Figure 2: Micelle formation

Main effects of quillaja saponins are: reduction of surface tension, formation of persistent foam, saponin- cholesterol complexes, emulsification of fats and oils, cellular and humoral immune responses, disruption of cell membranes, reduction of ammonia, activation of microbial growth.

There are over 300 scientific papers and international patents describing the use of quillaja saponins for different applications. Key words: quillaja, quillay, quillaia, saponins, saponinas, tensoactives, tensoactivos, panama bois.