Compositional and immunogenic evaluation of fractionated wheat beers using mass spectrometry. (15th December 2020)

• Record Type: Journal Article
• Authors: Cao, Wanying; Baumert, Joseph L.; Downs, Melanie L.
• Is Part Of: Food chemistry. Volume 333(2020)
• Publication Date: 2020-12-15
• Subjects: Wheat beers -- Fermentation -- Gluten -- Celiac disease -- Mass spectrometry -- Proteomics; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2020.127379
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Fractionation and custom informatics improved the proteomic analysis of wheat beers. Gluten accounted for different numbers of wheat (50%) and barley (20%) peptides. Up to 50% of identified peptides contained celiac-immunogenic motifs. Consumption of wheat beers presents risks for individuals with celiac disease. Abstract: The safety and regulatory status of fermented products derived from gluten-containing grains for patients with celiac disease remains controversial. Bottom-up mass spectrometry (MS) has complemented immunoassays for the compositional and immunogenic analyses of wheat beers. However, uncharacterized proteolysis during brewing followed by the secondary digestion for MS has made the analysis and data interpretation complicated. In this study, the composition and immunogenic potential of seven commercially available wheat beers were evaluated using bottom-up MS with the aid of fractionation and a multi-step peptide search strategy to identify peptides generated by various types of proteolysis. Gluten-derived peptides accounted for approximately 50% and 20% of the total number of wheat-derived and barley-derived peptides, respectively, in the investigated beers. Although relatively large polypeptides cannot be thoroughly characterized using traditional bottom-up proteomics, up to 50% of peptides identified contained celiac-immunogenic motifs, and consumption of wheat beers would pose risks for celiac patients.