Fermented marigold meal enhances muscle nutrition and flavor in white feathered broilers via gut microbiota...

Marigold (Tagetes erecta L.) residue, a by-product of industrial lutein extraction, is rich in carotenoids and polyphenols, offering potential as a poultry feed additive. This study employed Lactobacillus plantarum for solid-state fermentation of marigold meal and evaluated dietary inclusion (5 % or 10 %) in broilers for 42 days. Fermented marigold meal had no significant effects on growth performance or basic meat quality (pH, color, water-holding capacity) but improved breast muscle composition by increasing non-essential amino acids (e.g., glutamate, GABA), n-3 PUFAs, and PUFA/SFA ratio, while reducing MUFAs. 16S rRNA sequencing revealed enrichment of beneficial bacteria (Parabacteroides, Lactobacillus) and higher butyric acid levels. GC-MS identified 171 volatile compounds, with elevated key aroma compounds (e.g., 2(3H)-furanone, Geranylacetone) in marigold-fed groups, linked to altered microbiota. Fermented marigold meal enhances meat nutrition and flavor through gut microbiota-mediated pathways, providing a sustainable approach for high-value utilization of agricultural by-products.