Advances in Solid-State Fermentation Technology for Oilseed Meal: Strain Selection, Fermentation Strategies, and High-Value Applications
Oilseed meal, the primary by-product of oil extraction, is rich in protein, dietary fiber, and minerals, offering significant development potential. However, its application in high-value feed and food is severely restricted due to anti-nutritional factors, leading to resource waste and environmental issues. Solid-state fermentation (SSF) provides a green and efficient approach for the high-value utilization of oilseed meal. This review comprehensively discusses the entire process of strain selection, fermentation strategies, and application of active products in the SSF of oilseed meal. Regarding strain selection, Bacillus spp. degrade macromolecular proteins and inhibit microbial contamination through protease and antimicrobial peptide production. Lactobacillus spp. enhance flavor and safety by producing acids and flavor compounds. Aspergillus spp. decompose cell walls and degrade phytate using their cellulase and phytase systems. For fermentation strategies, mixed fermentation achieves functional complementarity, enzyme–fungus synergy enhances substrate conversion, segmented fermentation optimizes the microbial environment, and physical field assistance boosts enzyme activity, collectively improving fermentation efficiency and nutritional quality. In product applications, fermented oilseed meal serves as both high-quality protein feed and a source of functional peptides and active polysaccharides with antioxidant and immunomodulatory activities, showing potential for functional foods and biomedicine. In conclusion, SSF technology effectively degrades anti-nutritional factors, improving the nutritional value and adding value to oilseed meal, thus representing a key strategy for resource conversion. Future efforts should prioritize high-performance strain selection, intelligent process monitoring, and green preparation of active products to promote industrial application and sustainable development.