A synthetic or animal-derived ingredient (Paula’s Choice Skincare uses the former) that stabilizes the water phase of moisturizers and other skincare products that contain hydrating ingredients. Sodium stearoyl lactylate works via its interaction with proteins and starches, where it can also help modify a product’s texture.
It can also function as a surfactant.
Reference for this information:
Journal of Colloid and Interface Science, December 2016, pages 393-404