Production of HMOs using microbial hosts — from cell engineering to large scale production

•Since 2015, human milk oligosaccharides (HMOs) have become commercially available.•Major infant formula manufacturers have introduced HMOs in their products.•Manufacturing of HMOs is based on fermentation using engineered cells of E. coli.•Downstream processing is key to reach the high-quality demand on HMO end-products.•After 2’-FL and LNnT, a number of new HMO products are in the commercial pipeline.