Individual and interactive effects of heating temperature, sodium nitrite concentration, and simulated gastric conditions on nitrosamine formation in pork sausages

Nitrosamines are carcinogenic compounds formed during meat processing and digestion. This study examined the effects of heating temperature, nitrite concentration, and simulated gastric conditions (SGC) on NDMA, NPIP, and NPYR formation. A factorial design combined with partial least squares regression (PLSR) and interaction analysis was used to assess individual and combined effects. NDMA formation increased markedly under high-temperature and high-nitrite conditions, highlighting the importance of processing control. In contrast, NPIP and NPYR were mainly affected by SGC, with NPYR showing strong formation potential under digestive conditions. Interaction analysis revealed compound-specific effects not evident in single-variable models, underscoring distinct mechanistic pathways. These findings demonstrate that total nitrosamine measurements alone may not adequately reflect exposure risks. Instead, compound-specific evaluations are required to capture differences in precursors and formation tendencies, providing a more robust basis for risk assessment and targeted strategies to reduce dietary exposure.