In vitro digestion of nitrite and nitrate preserved fermented sausages – New understandings of nitroso-compounds’ chemical reactivity in the digestive tract
Résumé
In vitro digestions of dry-cured sausages formulated with four different rates of added sodium nitrite and sodium
nitrate (NaNO2 / NaNO3, in ppm: 0/0; 80/80; 120/120; 0/200) were performed with a dynamic gastrointestinal
digester (DIDGI®). The chemical reactivity of the potentially toxic nitroso-compounds (NOCs), oxidation reactions
products and different iron types were evaluated over time. No nitrite nor nitrate dose effect was
observed on NOCs’ chemical reactivity. Nitrosothiols were scarce, and nitrosylheme was destabilized for every
conditions, possibly leading to free iron release in the digestive tract. Total noN-volatile N-nitrosamines concentrations
increased in the gastric compartment while residual nitrites and nitrates remained stable. The
minimal rate of 80/80 ppm nitrite/nitrate was enough to protect against lipid oxidation in the digestive tract.
The present results provide new insights into the digestive chemistry of dry sausages, and into new reasonable
arguments to reduce the load of additives in formulations.
