Galacto-Oligosaccharides (GOS), also known as oligogalactosyllactose, oligogalactose or oligolactose, belong to the group of prebiotics. Prebiotics are defined as non-digestible food ingredients that beneficially affect the host by stimulating the growth and/or activity of beneficial bacteria in the colon.
The degree of polymerization of GOS can vary quite markedly, ranging from 2 to 8 monomeric units.