Several yeast and fungi are known to produce bioemulsifiers either intracellularly, cell bound, or extracellularly. Bioemulsifiers are mostly produced under excess carbon source and limited nitrogen source
with some exceptions where the bioemulsifier is a carbohydrate-protein complex. The type, quality, and quantity of emulsifier depends on microbial strain, carbon source, and media components such as
major and minor elements, temperature, pH etc.