Measurement of wheat gluten and barley hordeins in contaminated oats from Europe, and United States and Canada by Sandwich R5 ELISA

National Center of Biotechnology (Gluten Unit), Madrid, Spain.
European Journal of Gastroenterology & Hepatology (Impact Factor: 2.25). 07/2008; 20(6):545-54. DOI: 10.1097/MEG.0b013e3282f46597
Source: PubMed


We have investigated the extent of contamination with wheat, barley, rye or a mixture of these cereals in a large number of grains and commercial oats. We have also attempted to identify the type of cereal contaminant.
Sandwich R5 ELISA (using either gliadins or hordeins as standards), western blot, matrix-assisted laser desorption/ionization time-of-flight mass spectrometric and quantitative real-time PCR (Q-PCR) techniques have been used to analyze a total of 134 oats, comprising grains and commercial oat products collected from Europe, the United States and Canada.
Twenty-five of the 134 pure, uncontaminated oat varieties were found to have undetectable levels of gluten, whereas most of the 109 grains and commercial oat products were mainly contaminated with mixtures of wheat, barley and rye, barley being the predominant contaminant. The percentages of these cereals in the oat samples have been calculated by specific wheat, barley and rye Q-PCR systems. The oat samples were grouped according to the avenin spectra determined by the mass spectrometric technique. The data confirmed that contaminated oat foods, based on the same variety, could have different levels of wheat, barley and rye contamination.
This study has verified that contamination with wheat gliadins or barley hordeins in oat samples can be measured by the Sandwich R5 ELISA, using either gliadins or hordeins as standards, and also the importance of using confirmatory techniques (such as western blot, Q-PCR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) to confirm that most oats are contaminated with mixtures of wheat, barley and rye.

Download full-text


Available from: Jorge R Mujico,
212 Reads
  • Source
    • "Whether consumption of oats presents a hazard to celiacs has been a controversial subject for more than 50 years (Thompson, 2003). A major obstacle to the general acceptance of oats in celiac diets is a concern for contamination with wheat, rye or barley (Hernando, Mujico, Juanas, & Méndez, 2006; Hernando et al., 2008). Oats are inherently free of gluten (FDA, 2007) and the R5 Mendez ELISA used in this study is reported not to detect oat prolamin proteins. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Individuals with allergies and intolerances to grain products rely on accurate food labelling to prevent potentially life-threatening reactions. The aim of this study was to evaluate a number of South African food products for gluten and wheat to ascertain whether these products may pose a risk to celiac and/or wheat allergic individuals. Twenty-five products were analysed, including spelt products, flours of buckwheat, barley, rye, rice, millet, maize, semolina, triticale, oats, porridges, rice- and maize-based cereals, and rye bread. The rye and barley flours and two oat products were shown to be contaminated with wheat. Ten out of 17 naturally gluten-free products contained gluten, although in 13 of these the levels were below 20 mg/kg. The labels of four products were found to be misleading in terms of the gluten and/or wheat claims made.
    Food and Agricultural Immunology 06/2010; 21(2):91-102. DOI:10.1080/09540100903443725 · 0.99 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Celiac disease is an immune‐mediated disease, triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. The only treatment for celiac disease is a strict gluten‐free diet for life. This paper presents a systematic review of the scientific literature on the safety of pure oats for individuals with celiac disease, which historically has been subject to debate.Limitations identified within the scientific database include: limited data on long‐term consumption, limited numbers of participants in challenge studies, and limited reporting about the reasons for withdrawals from study protocols. Furthermore, some evidence suggests that a small number of individuals with celiac disease may be intolerant to pure oats and some evidence from in vitro studies suggests that an immunological response to oat avenins can occur in the absence of clinical manifestations of celiac disease as well as suggesting that oat cultivars vary in toxicity.Based on the majority of the evidence provided in the scientific database, and despite the limitations, Health Canada and the Canadian Celiac Association (CCA) concluded that the majority of people with celiac disease can tolerate moderate amounts of pure oats. The incorporation of oats into a gluten‐free diet provides high fiber and vitamin B content, increased palatability, and beneficial effects on cardiovascular health. However, it is recommended that individuals with celiac disease should have both initial and long‐term assessments by a health professional when introducing pure oats into a gluten‐free diet.
  • Source
Show more