Dietary substitution with space-mutated Arundo donax L. remodels carnitine-mediated lipid oxidation and improves mutton flavor in Hu sheep.

Space-mutated Arundo donax L. (SA) is a novel stress-tolerant forage crop developed through space-induced mutagenesis. The study aimed to investigate how SA modulates lamb flavor through carnitine-mediated lipid metabolic remodeling and alterations in volatile flavor profiles. In this study, thirty Hu lambs were randomly assigned to three dietary groups: control (CK), SA replacing alfalfa (T1), and SA replacing protein supplements (T2). As a result, lipidomics identified 1098 lipids, including 113 and 98 differential lipids in CK vs. T1 and CK vs. T2, respectively. HS-SPME-GC-MS detected 535 volatile compounds, with 201 and 30 differential volatile compounds, respectively. Relative odor activity value (ROAV) analysis identified 43 key odor-active compounds (ROAV ≥1). Correlation analysis revealed significant positive associations between acylcarnitines and key volatile compounds. These findings provide new insights into SA-mediated lipid metabolic remodeling and flavor regulation, supporting its potential as a nutritional strategy for improving lamb flavor.