Biotechnology in Dairy Alternatives: Current Perspectives on Fermentation Technologies for Replacing Regular Milk with Artificial Milk

Growing environmental concerns and ethical considerations have catalyzed unprecedented technological innovation in dairy alternatives, with precision fermentation emerging as a transformative methodology bridging traditional approaches. Unlike previous analyses that examine production technologies in isolation, this review presents the first integrated framework connecting milk's compositional complexity directly to production technology selection, economic viability assessment, and regulatory pathway determination. Through this multidimensional analytical lens, we provide critical analysis of artificial milk production strategies through complementary paradigms. The bottom-up approach engineers individual milk components including proteins, lipids, and carbohydrates using recombinant technologies, offering unprecedented compositional control but encountering structural complexity barriers. Conversely, the top-down approach employs mammary cell cultivation to replicate natural lactation systems, preserving native structural complexity while confronting significant scalability challenges. Precision fermentation represents a technological nexus between these methodologies, employing genetically engineered microorganisms to produce milk-identical components while retaining critical structural elements. Despite significant progress in casein and whey protein production demonstrating 95%-99% sequence identity with native proteins, substantial barriers remain in replicating quaternary structures like casein micelles and milk fat globule membranes. Economic viability represents another critical challenge, with current production costs for recombinant proteins ($210-310/kg) substantially exceeding conventional dairy ($15-25/kg). Environmental analyses suggest potential reductions of 91%-97% in greenhouse gas emissions and 78%-90% in land use through large-scale implementation. This review synthesizes recent innovations in human milk oligosaccharide synthesis, complex protein expression systems, regulatory framework development, and consumer acceptance dynamics, thereby providing an integrated perspective on artificial milk technological trajectory and market transformation potential.