Smoldering Smoke Conditions Affect Contents of Monochloropropanediols in Frankfurter-Type Sausages

Statistically designed smoldering smoke experiments with Frankfurter-type sausages were performed using 14 setups (two replicates, each). The target smoke generation temperatures (150, 300, 450, 600, 750, and 900 °C) were adjusted by air supply, and the actual temperatures were monitored over a smoking period of 3–15 min using three sensors placed in the ember bed. The contents of 3- and 2-monochloropropanediols (MCPD) in Frankfurters were analyzed and ranged between 2.7–60.6 and 0.2–1.7 μg/kg, respectively. The 3-MCPD/2-MCPD ratio ranged from 27 to 46 and was noticeably higher than reported for thermally processed foods. The MCPD levels were correlated with values derived from the temperature curves and the smoking time. For the first time, a correlation between the smoke generation temperature and the MCPD content was proven. Pearson’s correlations were obtained for the mean temperature of the three sensors over all time points with 0.921 (3-MCPD) and 0.947 (2-MCPD).