Analysis of Gluten in Dried Yeast and Yeast-Containing Products

Abstract

Yeast are commonly used in the preparation of foods and beverages such as beer and bread and may also be used on their own as a source of nutrients and flavoring. Because of the historical connection of yeast to products made from wheat and barley, consumers maintaining a gluten-free diet can have concerns about the safety of yeast ingredients. Analyzing the safety of yeast and yeast-containing products presents some difficulties, as the yeast organisms actively degrade any gluten in the product, raising questions on the appropriateness of detection by traditional antibody-based methods. This study examines a variety of yeast and yeast-containing products by competitive ELISA and liquid chromatography-mass spectrometry for the estimated level of gluten proteins. While samples such as yeast extracts and nutritional yeast contained gluten levels below the 20 mg/kg (or parts per million, ppm) threshold defined by Codex Alimentarius, one baking yeast and a nutritional yeast supplement sample contained higher levels of gluten. This study demonstrates that both competitive ELISA and liquid chromatography-mass spectrometry provide similar results in the detection of wheat and barley gluten in yeast-containing products.

Identification of gluten and the major milk allergens Bos d 5 and Bos d 11 within commercially available honey samples.

“…Brewer's yeast is known to contain residual levels of gluten from beer brewing. A study from Allred et al reported dried brewers' yeast to have a gluten content exceeding 270mg/kg [31], offering an explanation to the gluten detected in the honey samples. It is known caseins account for the majority (80%) of total milk protein [42], so it is surprising to detect less casein allergen than whey allergen present in the honey samples.…”

“…Supplementary feeding is one of the Beekeeping Management Practices implemented by beekeepers to maintain healthy honeybee colonies and to achieve agricultural and food production objectives. In some cases, Beekeepers tend to supplement with mixtures of soybean flour, dried brewer's yeast (which is known to contain gluten [31]), and dry skimmed milk with sugar and water [32][33][34].…”

Microbe‐Mediated Biosynthesis of Multidimensional Carbon‐Based Materials for Energy Storage Applications

“…Yeasts are a group of unicellular microorganisms that can propagate by budding or cleavage, and both survive in aerobic and anaerobic environments. The use of yeast can be traced back to four thousand years ago [ 81 ] in brewing, food and pharmaceutical industries, usually for fermentation, beer brewing, and alcohol manufacturing. Yeasts consisting of numerous proteins and vitamins that can not only be used as medicinal yeast tablets and feed additives, but also as an ideal raw material for the production of single‐cell protein, extraction and preparation of nucleotide, coenzyme A, cytochrome C, and amino acids.…”

Yarrowia lipolytica as an Alternative and Valuable Source of Nutritional and Bioactive Compounds for Humans

“…Additionally, it is recognized that Y. lipolytica protein biomass is gluten-free. It is proven that the nutritional yeast products, i.e., the protein biomass, contained gluten at below the 20 mg/kg threshold defined by the Codex Alimentarius, The Codex, or the Gluten-Free Certification Organization (GFCO) [ 213 ].…”