Allergen Targets

Tree nuts

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Food Matrices

Walnut milk

Anchovy walnut stir-fry

Stir-fried nuts pepper sauce

Walnut almond barley tea

Walnut pie

Soy

Chicken

Discovery, verification, and validation of walnut protein marker peptides using LC-MS approaches

Kim, K., Kim, Y., Lee, H., Lee, C., Kim, S., Oh, S. and Park, Z.-Y.

Food Chemistry (2023), 429, 136889 DOI: 10.1016/j.foodchem.2023.136889

Abstract

A key requirement of liquid chromatography-mass spectrometry (LC-MS)-based allergenic food protein analysis methods is to use protein marker peptides with good analytical performances in LC-MS analysis of commercial processed foods. In this study, we developed a multi-stage walnut protein marker peptide selection strategy involving marker peptide discovery and verification and LC-MS validation of chemically equivalent stable isotope-labeled peptides. This strategy proposed three walnut protein marker peptides, including two new marker peptides. Our LC-MS-based walnut protein analysis method using the three stable isotope-labeled peptides showed acceptable linearity (R2 >0.99), matrix effects (coefficient of variation <±15%), sensitivity (limit of detection >0.3 pg/μL, limit of quantification >0.8 pg/μL), recovery (85.1–103.4%), accuracy, and precision (coefficient of variation <10%). In conclusion, our multi-stage marker peptide selection strategy effectively selects specific protein marker peptides for sensitive detection and absolute quantification of walnut proteins in LC-MS analysis of commercial processed foods.

Reference raw data

Reference ID	Food	Protein	Peptide
87	Walnut	Jug r 2	VPAGATVYVINQDSNER