Investigation of low molecular weight peptides (<1 kDa) in chicken meat and their contribution to meat flavor formation

Abstract BACKGROUND Low molecular weight peptides (LMWPs) (<1 kDa) generated in meat during chilled conditioning can act as flavor precursors in the Maillard reaction with a potential contribution to key volatile organic compound (VOC) formation upon heating. Liquid chromatography/quadrupole time‐of‐flight mass spectrometry (LC/QTOF‐MS) successfully detected 44 LMWPs in chicken breast and thigh muscles stored at 4 °C for up to 6 days. Carnosine (350 mg per 100 g), glutathione (GSH, 20 mg per 100 g) (concentrations based on reported values in the literature) and cysteine glycine (Cys Gly, 5 mg per 100 g) (concentration based on results from LC/QTOF‐MS) were used in model systems containing ribose (25 mg per 100 g). The three model systems were heated at 180 °C for 2 h at pH 6.3. VOCs were measured by simultaneous distillation solvent extraction/gas chromatography/mass spectrometry. RESULTS Of 33 VOCs detected, 26 were significantly different ( P ≤ 0.05) between the three peptides. The majority of nitrogen‐containing volatiles, pyrazines and pyridines, dominated the carnosine mixture, while sulfur‐containing VOCs dominated the GSH and Cys Gly peptide mixtures. CONCLUSION Known key aroma compounds such as thiazole (meaty), 2‐methyl‐3‐furanthiol (beef and meat), 2‐furfurylthiol (roasted), dihydro‐2‐methyl‐3(2 H )‐thiophenone (meaty), 2‐acetylthiazole (meaty and roasted) and pyrazine (meaty) were detected under conditions specific to aged and thermally treated chicken, suggesting a potential contribution to the overall sensory quality of cooked meat. © 2018 Society of Chemical Industry