R1 - Detection and quantification of 4-oxo-2-nonenal in plant-based meat and beef

Oxidative degradation of lipids and proteins in food causes loss of nutrition, produces genotoxic oxidative byproducts, and increases health concerns. 4-Oxo-2-nonenal (4-ONE) is a highly reactive and toxic aldehyde, recently identified as a novel lipid peroxidation byproduct. However, naturally formed 4-ONE and its interaction with proteins in food are still not fully understood. In this study, methods for the detection and quantification of 4-ONE were further developed and used. The developed method successfully detected the formed lipid oxidation products (LOPs) and protein oxidation products (POPs) during cooking, as well as after in-vitro digestion of plant-based (PB) meat and beef. The method used exhibited consistencies of detection of 4-ONE in raw, cooked, and in-vitro digested PB meat and beef samples. Furthermore, the findings of this study show that PB meat had significantly higher levels of POPs but lower levels of aldehydes (4-ONE and malondialdehyde) than beef samples. The results revealed the LC–MS/MS method for detecting and quantifying 4-ONE as a novel lipid oxidation marker was promising. Furthermore, the results indicated that the protein in PB meat may be prone to covalent modification of aldehyde and free radical attacks, thus reducing its proteolysis during digestion. Future studies should further assess the covalent binding ability of aldehydes (especially 4-ONE) in different types of protein, as well as the interaction between lipid and protein oxidation. Processors should develop new strategies to avoid undesirable LOPs and POPs in PB meat and beef, to improve their nutrition and relieve long-term health concerns.