What it is
This ingredient is the filtered liquid obtained after Lactobacillus bacteria are cultured on soymilk and the bacterial cells are removed. The fermentation of soy proteins and sugars generates amino acids, peptides, and organic acids that condition and hydrate the skin surface. It is incorporated into the water phase of leave-on formulas, often in ferment- or fermentation-themed products.
Safety & warnings
Generally well tolerated in leave-on skincare. It is derived from soy, so individuals who deliberately avoid soy-based ingredients should note its source; overall tolerability depends on the finished formula.
Origin & sourcing
Biotechnological: lactic-acid bacterial fermentation of soymilk (soybean milk), after which the microbial cells are filtered out to leave the filtrate.
Questions everyone asks
What is the source of this ingredient?
It is made by fermenting soymilk with Lactobacillus bacteria and then filtering out the cells.
What does it do in a product?
It works as a humectant and skin-conditioning ferment active, not as a UV filter.