Abstract:

Under the current context of soybean meal reduction and substitution, the development of novel protein feed resources has become a crucial task for sustainable development in animal husbandry. As a protein-rich brewing byproduct, Huangjiu lees can be converted into high-quality feed raw materials through microbial fermentation technology. This study successfully screened superior strains (B29, Yzz, and L1) with good cellulose degradation ability, high protease activity, and strong acid production function from Huangjiu lees, identified as Bacillus pumilus, Saccharomyces cerevisiae, and Enterococcus faecium respectively. By employing mixed microbial fermentation, we further investigated the improvement effects of mixed microbial synergistic fermentation on the nutritional value of Huangjiu lees feed. The results revealed that the microbial combination B29+Yzz+L1 significantly enhanced nutritional value of Huangjiu lees feed, moisture content, lactic acid content, crude protein content, and acid-soluble protein content increased by 4.00 percentage points, 51.11%, 8.27%, and 38.52% respectively, while pH value decreased by 5.08%, viable bacterial count reached 9.3×10⁸ CFU·g^-1 after fermentation. These findings provide a novel approach for resource utilization of Huangjiu lees, providing significant implications for alleviating protein feed shortages and promoting green development in animal husbandry.

Key words: soybean meal reduction, protein feed, Huangjiu lees, mixed microbial synergistic fermentation