Gluten-containing grains skew gluten assessment in oats due to sample grind non-homogeneity.
Oats are easily contaminated with gluten-rich kernels of wheat, rye and barley. These contaminants are like gluten 'pills', shown here to skew gluten analysis results. Using R-Biopharm R5 ELISA, we quantified gluten in gluten-free oatmeal servings from an in-market survey. For samples with a 5-20ppm reading on a first test, replicate analyses provided results ranging <5ppm to >160ppm. This suggests sample grinding may inadequately disperse gluten to allow a single accurate gluten assessment. To ascertain this, and characterize the distribution of 0.25-g gluten test results for kernel contaminated oats, twelve 50g samples of pure oats, each spiked with a wheat kernel, showed that 0.25g test results followed log-normal-like distributions. With this, we estimate probabilities of mis-assessment for a 'single measure/sample' relative to the <20ppm regulatory threshold, and derive an equation relating the probability of mis-assessment to sample average gluten content.
PepsiCo, Inc. Global R&D, Measurement Sciences, 617 W. Main Street, Barrington, IL 60010, USA. Electronic address: ronald.fritz@pepsico.com.
Ronald D
RD
Fritz
PepsiCo, Inc. Global R&D, Measurement Sciences, 617 W. Main Street, Barrington, IL 60010, USA.
Yumin
Y
Chen
PepsiCo, Inc. Global R&D, Foods Breakfast, 617 W. Main Street, Barrington, IL 60010, USA.
Veronica
V
Contreras
D018554:Avena / Q000737:chemistry*; D002523:Edible Grain / Q000737:chemistry*; D005983:Glutens / Q000032:analysis*; D001467:Hordeum / Q000737:chemistry; D006801:Humans; D014908:Triticum / Q000737:chemistry
D005983:Glutens
ELISA; Gluten; Gluten analysis; Gluten measurement; Gluten-free; Kernel-based gluten contamination; Oat