# Proteomics Analysis of Celiac Disease-Active Peptides in Food Products with Partially Hydrolyzed Gluten

## TL;DR

This study identifies harmful gluten peptides in food products with partially hydrolyzed gluten, showing they can still trigger celiac disease.

## Contribution

The study quantifies celiac disease-active peptides in various food products using advanced proteomics techniques.

## Key findings

- Barley malt extracts had the highest concentrations of celiac disease-active peptides, ranging from 481 to 1305 mg/kg.
- Peptide concentrations in soy sauce were much lower, ranging from 0.2 to 0.5 mg/kg.
- Peptide levels correlated with gluten content measured by ELISA in barley-based products but not in soy sauce.

## Abstract

Foods with partially hydrolyzed gluten may still trigger
immune
responses in celiac disease (CeD) patients due to residual CeD-active
peptides. We applied nanoliquid chromatography-tandem mass spectrometry
(nanoLC-MS/MS) to identify 54 CeD-active peptides in 15 barley malt
extracts (BME), seven barley malt vinegars (BMV), and 15 soy sauces.
Eight common CeD-active peptides were quantitated with targeted nanoLC-MS/MS
and stable isotope dilution assay. Total peptide concentrations ranged
from 481 mg/kg to 1305 mg/kg in BMEs, whereas three samples showed
peptide concentrations near LOQ. Six BMVs had peptide concentrations
of up to 0.04 mg/kg, and in soy sauce, they ranged from 0.2 mg/kg
to 0.5 mg/kg. Peptide concentrations correlated with gluten content
measured by R5c ELISA in BMEs and BMV, while soy sauce showed a gluten
content below the LOQ by ELISA. These findings show the presence of
CeD-active peptides in foods containing partially hydrolyzed gluten,
highlighting the need for comprehensive risk assessment.