It serves as a nutrient-rich medium for microbial fermentation (antibiotics vitamin B12 lysine enzymes) animal feed additive (up to 15% in cattle rations) and bioprocessing for organic acids.

Its primary purpose is providing complex nitrogen sources growth factors and carbohydrates that promote microbial growth more effectively than purified media while offering economical proteinphosphorus in livestock nutrition.

Corn steep liquor (CSL) is a viscous tan-brown liquid byproduct from corn wet-milling where corn kernels are steeped in water with sulfur dioxide containing 50% water plus soluble extracts like proteins (25% wet basis) lactic acid (14%) amino acids vitamins reducing sugars and minerals.