C -Nitrosation, C -Nitration, and Coupling of Flavonoids with N -Acetyltryptophan Limit This Amine N -Nitrosation in a Simulated Cured and Cooked Meat.

Nitrite is a common additive in cured meat formulation that provides microbiological safety, lipid oxidation management, and typical organoleptic properties. However, it is associated with the formation of carcinogenic N -nitrosamines. In this context, the antinitrosating capacity of selected flavonoids and ascorbate was evaluated in a simulated cooked and cured meat under formulation and digestion conditions. N -Acetyltryptophan was used as a secondary amine target. (-)-Epicatechin, rutin, and quercetin were all able to limit the formation of N -acetyl- N -nitrosotryptophan ( NO -AcTrp) at pH 2.5 and pH 5 although (-)-epicatechin was 2 to 3-fold more efficient. Kinetics for the newly identified compounds allowed us to unravel common mechanistic pathways, which are flavonoid oxidation by nitrite followed by C -nitration and an original covalent coupling between NO -AcTrp and flavonoids or their nitro and nitroso counterparts. C -nitrosation of the A-ring was evidenced only for (-)-epicatechin. These major findings suggest that flavonoids could help to manage N -nitrosamine formation during cured meat processing, storage, and digestion.