Utilization of animal by-products as sources of bioactive compounds and FBS alternatives for cultured meat: a comprehensive review

Slaughterhouse by-products have been widely utilized in food, pharmaceutical, and biomaterial applications across Asia, Europe, and the Americas. This review examines current research on enhancing the value and utilization of these by-products, with a particular focus on their potential as alternatives to fetal bovine serum (FBS), a critical component of cell culture media. Among these, livestock and poultry blood-produced at over 30 million tons annually-is of particular interest; however, only approximately 30% is currently used in food products or additives. Recent studies suggest that serum derived from bovine, porcine, and chicken blood may serve as viable substitutes for FBS. Recent studies have suggested that serum derived from adult bovine, porcine, and chicken blood may partially substitute for FBS, with replacement efficiencies reported to reach up to approximately 80%, depending on the species. Inedible by-products, including feathers, bones, leather, and hooves, are primarily processed into fertilizers and animal feed due to their high protein and mineral content. Despite the considerable volume of slaughter by-products generated, their application in cell culture systems and other high-value industries remains underdeveloped. Promoting the industrial utilization of these materials could not only improve resource efficiency and reduce environmental impact but also contribute to the sustainability and economic value of the livestock sector.