Dual-action mechanism of Tamarix polyphenols in inhibiting IQ and MeIQ: Synergistic scavenging of free radicals and trapping of reactive carbonyls.

Tamarix lamb skewers are highly favored for its distinctive flavor profile, with polyphenol-rich Tamarix branches demonstrating inhibitory effects on heterocyclic amine (HAs) formation during lamb roasting. Four major polyphenols were evaluated for suppressing 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ) and 2-amino-3,4-dimethyl-imidazo[4,5-f]quinoline (MeIQ) in chemical models and lamb patties. Mechanistic investigations employed Electron Spin Resonance (ESR) to quantify radical scavenging capacity and UPLC-MS/MS to assess reactive carbonyl (acrolein/crotonaldehyde) trapping efficiency. Quercetin showed peak inhibition of 65.97 % (IQ in patties) and 83.98 % (MeIQ in models). Hispidulin exhibited superior radical scavenging (over 90 % reduction at level), while isorhamnetin displayed optimal carbonyl-trapping performance at level, and a total of eight distinct mono- and di-adducts structurally were characterized. Linear regression analysis confirmed synergistic inhibition mechanisms via free radical scavenging and reactive carbonyl trapping. This study proposes a dual-action mechanism for natural HAs mitigation, advancing strategies to reduce thermal-processed food hazards.