Heat-induced modification of amino acid residues in beef patties at different temperatures (150 °C, 190 °C, 230 °C, 270 °C and 310 °C).a.
| Residue | Sequence | Modification | Treatment | |||||
|---|---|---|---|---|---|---|---|---|
| Control | 150 °C | 190 °C | 230 °C | 270 °C | 310 °C | |||
| Cysteine | C̲PETLFQPSFIGMESAGIHETTYNSIMKC | Oxidation | ✓ | ✓ | ||||
| Dioxidation | ✓ | |||||||
| Proline | CP̲ETLFQPSFIGMESAGIHETTYNSIMKC | Dioxidation | ✓ | |||||
| Phenylalanine | CPETLF̲QPSFIGMESAGIHETTYNSIMKC | Oxidation | ✓ | ✓ | ✓ | ✓ | ||
| Serine | CPETLFQPS̲FIGMESAGIHETTYNSIMKC | Dehydration | ✓ | ✓ | ||||
| Phenylalanine | CPETLFQPSF̲IGMESAGIHETTYNSIMKC | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ✓ | |||
| Trioxidation | ✓ | |||||||
| Methionine | CPETLFQPSFIGM̲ESAGIHETTYNSIMKC | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | |||||
| Tyrosine | CPETLFQPSFIGMESAGIHETTY̲NSIMKC | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ||||
| Methionine | CPETLFQPSFIGMESAGIHETTYNSIM̲KC | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ✓ | |||
| Lysine | CPETLFQPSFIGMESAGIHETTYNSIMK̲C | Acetyl | ✓ | ✓ | ||||
| Carboxymethylation | ✓ | ✓ | ✓ | ✓ | ||||
| Serine | TTGIVLDS̲GDGVTHNVPIYEGYALPHAIMRLDLAGR | Dehydration | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Tyrosine | TTGIVLDSGDGVTHNVPIY̲EGYALPHAIMRLDLAGR | Trioxidation | ✓ | |||||
| Proline | TTGIVLDSGDGVTHNVPIYEGYALP̲HAIMRLDLAGR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | |||||
| Arginine | TTGIVLDSGDGVTHNVPIYEGYALPHAIMR̲LDLAGR | MDA | ✓ | ✓ | ||||
| Tryptophan | IW̲HHTFYNELR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Trioxidation | ✓ | ✓ | ✓ | ✓ | ||||
| Kynurenin | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Histidine | IWH̲HTFYNELR | Trioxidation | ✓ | ✓ | ✓ | |||
| Histidine | IWHH̲TFYNELR | Oxidation | ✓ | ✓ | ||||
| Arginine | IWHHTFYNELR̲ | MDA | ✓ | |||||
| Histidine | H̲QGVMVGMGQKDSYVGDEAQSK | Oxidation | ✓ | ✓ | ✓ | |||
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ✓ | |||
| Methionine | HQGVM̲VGMGQKDSYVGDEAQSKR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ||||
| Lysine | HQGVMVGMGQK̲DSYVGDEAQSKR | Acetyl | ✓ | |||||
| Carboxymethylation | ✓ | |||||||
| Tyrosine | HQGVMVGMGQKDSY̲VGDEAQSKR | Oxidation | ✓ | ✓ | ✓ | ✓ | ||
| Dioxidation | ✓ | |||||||
| Lysine | HQGVMVGMGQKDSYVGDEAQSK̲R | Acetyl | ✓ | ✓ | ||||
| Cysteine | LC̲YVALDFENEMATAASSSSLEK | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Dioxidation | ✓ | |||||||
| Tyrosine | LCY̲VALDFENEMATAASSSSLEK | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Methionine | LCYVALDFENEM̲ATAASSSSLEK | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ||||||
| Lysine | LCYVALDFENEMATAASSSSLEK̲ | Acetyl | ✓ | ✓ | ✓ | |||
| Carboxymethylation | ✓ | ✓ | ||||||
| Proline | VAP̲EEHPTLLTEAPLNPKANR | Oxidation | ✓ | |||||
| Proline | VAPEEHP̲TLLTEAPLNPKANR | Oxidation | ✓ | ✓ | ||||
| Histidine | VAPEEH̲PTLLTEAPLNPKANR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ||||
| Trioxidation | ✓ | ✓ | ||||||
| Proline | VAPEEHP̲TLLTEAPLNPKANR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Lysine | VAPEEHPTLLTEAPLNPK̲ANR | Carboxyethylation | ✓ | |||||
| MDA | ✓ | |||||||
| Arginine | VAPEEHPTLLTEAPLNPKANR̲ | MDA | ✓ | |||||
| Lysine | K̲DLYANNVMSGGTTMYPGIADR | Acetyl | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Carboxymethylation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Carboxyethylation | ✓ | ✓ | ||||||
| AAS | ✓ | |||||||
| Carbonylation | ✓ | ✓ | ✓ | ✓ | ||||
| Tyrosine | KDLY̲ANNVMSGGTTMYPGIADR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Methionine | KDLYANNVM̲SGGTTMYPGIADR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Dioxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ||
| Serine | KDLYANNVMS̲GGTTMYPGIADR | Dehydration | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Methionine | KDLYANNVMSGGTTM̲YPGIADR | Oxidation | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
| Proline | EITALAP̲STMKIKIIAPPERK | Oxidation | ✓ | ✓ | ||||
| Lysine | GILTLK̲YPIEHGIITNWDDMEK | Carboxyethylation | ✓ | |||||
| Proline | GILTLKYP̲IEHGIITNWDDMEK | Dioxidation | ✓ | |||||
| Histidine | GILTLKYPIEH̲GIITNWDDMEK | Dioxidation | ✓ | |||||
| Phenylalanine | AVF̲PSIVGRPR | Oxidation | ✓ | |||||
| Proline | AVFP̲SIVGRPR | Oxidation | ✓ | |||||
| Tryptophan | YPIEHGIITNW̲DDMEKIWHHTFYNELR | Trioxidation | ✓ | |||||
| Lysine | YPIEHGIITNWDDMEK̲IWHHTFYNELR | Acetyl | ✓ | ✓ | ✓ | |||
| Carboxymethylation | ✓ | |||||||
| Carboxyethylation | ✓ | ✓ | ||||||
| Lysine | EK̲LCYVALDFENEMATAASSSSLEK | Acetyl | ✓ | ✓ | ||||
| Carboxyethylation | ✓ | |||||||
| Lysine | RGILTLK̲YPIEHGIVTNWDDMEKIWHHTFYNELR | AAA | ✓ | ✓ | ✓ | ✓ | ||
| AAA | ✓ | |||||||
| Lysine | RGILTLKYPIEHGIVTNWDDMEK̲IWHHTFYNELR | Oxidation | ✓ | |||||
| Methionine | DLTDYLM̲KILTER | AAA | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Lysine | KVKSEK̲ADKLLK | AAS | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Lysine | K̲GEISELLVGSPSIR | AAS | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Lysine | SNSLVSSFPMEK̲R | MDA | ✓ | |||||
| Arginine | PR̲HQGVMVGMGQK | MDA | ✓ | |||||
| Arginine | FR̲CPETLFQPSFIGMESAGIHETTYNSIMK | MDA | ✓ | ✓ | ||||
| Arginine | ILTER̲GYSFVTTAER | MDA | ✓ | ✓ | ||||
| Arginine | AGFAGDDAPR̲AVFPSIVGR | MDA | ✓ | ✓ | ||||
| Arginine | GYSFVTTAER̲EIVR | MDA | ✓ | |||||
| Arginine | SYELPDGQVITIGNER̲FR | MDA | ✓ | |||||
a
✓ means that the corresponding modification type was detected in the sample at the corresponding temperature. Blank means not detected. The bold and underlined letters in the peptide sequence indicate the modified amino acid residues.