A multiplex competitive ELISA for the detection and characterization of gluten in fermented-hydrolyzed foods

Abstract

A novel competitive ELISA was developed utilizing the G12, R5, 2D4, MIoBS, and Skerritt antibody-HRP conjugates employed in nine commercial ELISA test kits that are routinely used for gluten detection. This novel multiplex competitive ELISA simultaneously measures gliadin-, deamidated gliadin-, and glutenin-specific epitopes. The assay was used to evaluate 20 wheat beers, 20 barley beers, 6 barley beers processed to reduce gluten, 15 soy sauces, 6 teriyaki sauces, 6 Worcestershire sauces, 6 vinegars, and 8 sourdough breads. For wheat beers, the apparent gluten concentration values obtained by the G12 and Skerritt antibodies were typically higher than those obtained using the R5 antibodies. The sourdough bread samples resulted in higher apparent gluten concentration values with the Skerritt antibody, while the values generated by the G12 and R5 antibodies were comparable. Although the soy-based sauces showed non-specific inhibition with the multiple R5 and G12 antibodies, their overall profile was distinguishable from the other categories of fermented foods. Cluster analysis of the apparent gluten concentration values obtained by the multiplex competitive ELISA, as well as the relative response of the nine gluten-specific antibodies used in the assay to different gluten proteins/peptides, distinguishes among the different categories of fermented-hydrolyzed foods by recognizing the differences in the protein/peptide profiles characteristic of each product. This novel gluten-based multiplex competitive ELISA provides insight into the extent of proteolysis resulting from various fermentation processes, which is essential for accurate gluten quantification in fermented-hydrolyzed foods. Graphical abstract A novel multiplex competitive ELISA for the detection and characterization of gluten in fermented-hydrolyzed foods.

Safety of occasional ingestion of gluten in patients with celiac disease: a real-life study

“…The intake of gluten from each food category was estimated on the basis of conversion factors (8.9 g gluten/ 100 g wheat flour, 4.2 g from barley, 3.0 g from rye, and 1.29 from oats) [27]. When analyzing beer consumption, the gluten content was obtained using a specific conversion factor, 0.00185 mg gluten/ml beer [28].…”

Multi-laboratory validation of the xMAP—Food Allergen Detection Assay: A multiplex, antibody-based assay for the simultaneous detection of food allergens

“…The allergen food mixtures incurred into the foods were derived from nonfat dried milk (NFDM) that was multi-analyst validated with multiple commercial ELISA test kits to perform comparable to NIST SRM 1549; NIST SRM 2387 peanut butter; wheat gluten (cat # G5004, Sigma-Aldrich Co.) that has been previous used in analytical studies [ 13 , 14 ]; organic, dry soy beans a product of ChoripDong (distributed by Seoul Shik Poom, Inc., Flushing NY, USA). Raw, organic (no shell) almonds, hazelnut, and walnuts, and the organic, shredded coconut; were acquired from Nuts.com.…”

“…The baked muffin samples were stored at 4˚C and shipped on ice, while the dark chocolate samples were stored and shipped at room temperature. In addition to the coded, incurred food samples, all participants were supplied with analyte-free food samples and reference materials (i.e., NIST SRM 2387 peanut reference material, non-fat dried milk reference material multi-analyst validated as comparable to NIST SRM 1549 using ELISA test kits, and wheat gluten reference material used for ELISA studies [13,14]) for preparing the DCCs.…”

Detection and Quantitation of Gluten in Fermented-Hydrolyzed Foods by Antibody-Based Methods: Challenges, Progress, and a Potential Path Forward

“…The regulatory threshold of 20 ppm intact gluten was based on studies examining the immunopathogenicity of intact gluten. Whether the biological activity is the same for gluten peptides that are produced during fermentation is unknown (29, 56–59).…”