Enzyme immunoassay and proteomic characterization of troponin I as a marker of mammalian muscle compounds in raw meat and some meat products

• Sandwich ELISA for quantification of muscle protein troponin I has been developed.
• The troponin I as a heat-stable protein is a suitable biomarker of meat sources.
• The developed method reveals mammalian meat, but not poultry meat.
• ELISA and electrophoretic data of troponin I estimations accord well.

The skeletal muscle protein troponin I (TnI) has been characterized as a potential thermally stable and species-specific biomarker of mammalian muscle tissues in raw meat and meat products. This study proposed a technique for the quantification of TnI comprising protein extraction and sandwich enzyme-linked immunosorbent assay (ELISA). The technique is characterized by a TnI detection limit of 4.8 ng/ml with quantifiable concentrations ranging from 8.7 to 52 ng/ml. The method was shown to be suitable for detection of TnI in mammalian (beef, pork, lamb, and horse) meat but not in poultry (chicken, turkey, and duck) meat. In particular, the TnI content in beef was 0.403 ± 0.058 mg/g of wet tissue. The TnI estimations obtained for the pork and beef samples using ELISA were comparable to the proteomic analysis results. Thus, the quantitative study of TnI can be a convenient way to assess the mammalian muscle tissue content of various meat products.