Two-stage solid-state fermentation to increase the nutrient value of corn processing waste and explore its efficacy as a feed protein source

Corn gluten meal-corn husk mixes (CCM) are an inexpensive and readily available agricultural by-product. This study explores a novel technique by converting CCM into high-value livestock feed protein sources through fermentation with Aspergillus niger AAX and Lactobacillus fermentum LLS, aiming to sustainably meet future global protein needs. The process of fermentation significantly altered the structural composition of high molecular weight proteins, zein, and dietary fibers. This transformation resulted in a marked elevation in the concentrations of peptides, free amino acids, and polyphenols. The acidic environment produced during fermentation prevented lipid oxidation in CCM, thereby extending its storability. After fermentation, the content of anti-nutritional factors decreased, while its antioxidant capacity increased. In vitro simulated digestion suggested that fermentation improved the digestibility of CCM protein. In vivo animal experiments showed that fermented CCM (FCCM) promoted growth and gut health in chicks. This study provides new insights into the utilization of CCM.