Evaluation of the Formation of Six Beta-Carboline Alkaloids, a Class of Natural Toxins, in Meat Products Using Liquid Chromatography Tandem Mass Spectrometry

Beta-carboline alkaloids (βC-alkaloids) are natural toxins found in various foods, and can also form during the thermal processing of protein-rich ingredients. This study investigated the formation of six βC-alkaloids in pork belly, beef sirloin, mackerel, and cutlassfish subjected to pan-frying, boiling, steaming, and air-frying at 170–250 °C for 2–24 min. Microwave pretreatment (1–5 min) was applied prior to cooking to assess its mitigation potential. Quantification was performed using liquid chromatography tandem mass spectrometry (LC-MS/MS). Pan-frying significantly promoted βC-alkaloid formation, with harman and norharman levels reaching up to 534.63 µg/kg and 217.06 µg/kg in beef sirloin, and 212.44 µg/kg and 533.01 µg/kg in cutlassfish, respectively. Air-frying generated lower alkaloid levels overall compared to pan-frying. Microwave pretreatment effectively mitigated alkaloid formation. The pretreatment of beef sirloin for 2 min resulted in a reduction in the norharman and harmaline levels by 78.4% and 96.5%, respectively. This study provides a comprehensive comparison of six βC-alkaloids across various food types and cooking methods, demonstrating the influence of cooking parameters on alkaloid formation. This study underscores the importance of understanding the thermal formation of natural toxins in foods and offers insight into practical strategies to minimize their occurrence in daily diets.