Current research on cellobiose 2-epimerase: enzymatic properties, mechanistic insights, and potential applications in the dairy industry

•Cellobiose 2-epimerase (CE) is an important tool for functional disaccharides production.•The enzymatic properties of all reported CEs are comprehensively discussed.•Discussed the epimerization and isomerization mechanisms of CEs based on crystal structures.•Reported the properties and production methods of two primary CE-involving products, epilactose and lactulose.