Validation of the OnSite® Gluten Test Kit for Detection of Gluten in Selected Foods and Environmental Surfaces: AOAC Performance Tested MethodSM 012501

Abstract

Background: The OnSite® Gluten Test Kit is a qualitative immunochromatographic assay designed for the detection of gluten in foods and on environmental surfaces.

Objective: To validate the performance of the OnSite Gluten Test Kit in rice flour, oat flour, spice mix, and bread, and on stainless steel surface.

Methods: The kit was assessed for cross-reactivity, interference, detection capability of spiked and incurred gluten, recovery from stainless steel surfaces, lot-to-lot consistency, robustness, and stability.

Results: Testing revealed no cross-reactivity or interference from a panel of gluten-free food items, or susceptibility to high analyte concentration. Analysis of selected spiked or incurred test materials at various estimated concentrations of gluten supported claimed detection capabilities (CDC) ranging from 5 to 20 mg/kg gluten depending on the aliquot volume and food matrix. The method detected wheat gluten present on stainless steel at a contamination level of 11 µg gluten/100 cm2 (POD 0.95, CI 0.76-1.00). Testing results also indicated consistency, robustness, and kit stability. Independent laboratory testing of select food matrixes supported the findings of the candidate laboratory.

Conclusions: The performance of the OnSite Gluten Test Kit was validated on gluten spiked or incurred into rice flour, oat flour, spice mix, and bread, and on stainless steel surfaces.

Highlights: The OnSite Gluten Test Kit offers an easy-to-use assay method to detect gluten in select foods and on stainless steel surfaces. The testing format affords the user flexibility in their choice of gluten detection thresholds.