A Rapid and Robust Targeted Proteomics Method for the Quantitation of Cross-Contaminations and Adulterations with Meat in Vegan and Vegetarian Meat Analogues

Plant-based meat analogues are becoming increasingly popular in industrialized countries and provide significant economic growth potential for established manufacturers of meat products and gastronomy. However, preparing meat analogues and meat in the same facility carries the risk of cross-contamination of the former. We therefore developed a targeted proteomics approach using LC-MS/MS and cross-species marker peptides with the potential to quantify meat in vegan and vegetarian foods. Protein extraction and digestion were optimized for rapid, simplified, and highly efficient sample preparation. Three matrix calibrations (0.1-5.0% w/w meat, each) were applied to vegan sausages and burger patties spiked with pork, chicken, or beef meat. The four markers DFNMPLTISR, DLEEATLQHEATAAALR, IQLVEEELDR, and LDEAEQLALK showed the highest accuracies for the determination of meat contents (recovery rates of 80-120%), allowing for reliable results with limits of quantitation below the commonly applied threshold of 0.1% w/w meat for its unintended presence.