AOAC Gluten Quantitative Validation Guidance-Round 1(Nov 2023)

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ISO 5725-1:2023, Accuracy (trueness and precision) of measurement methods and results—Part I: General principles and

definitions

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Koerner et al. (2013) JAOAC 96 (5), 1033-1040.

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USP 31:2008, U.S. Pharmacopeia General Information/ Validation of Alternative Microbiological Methods

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Definitions

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3.1 Analyte :

Chemical entity or entities measured by the measurement system, which may be a marker (e.g. a specific gluten peptide or 94 protein) or a surrogate (e.g. another protein from wheat, rye, barley or oats that correlates with the presence of gluten). 95  See also “Measurand” definition. See De Bievre 2013 for a detailed discussion of the difference between “analyte” and 96 “measurand”.

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3.2 Bias:

100 contrasted to random error. There may be one or more systematic error components contributing to the bias. 101 3.3 Calibrant: 102 A material used for calibration of a measurement procedure 103 3.4 Candidate Method: 104 The method submitted for validation. 105 3.5 Candidate Method Result: 106 The final results of the quantitative analysis for the candidate method. 107 3.6 Collaborator: 108 An intended user who participates in the collaborative study. 109 3.7 Cross-reactivity: 110 A measurable response, above the LOQ of the method, to a material other than the target analyte. 111 3.8 Cross-reactivity Study: 112

Difference between the expectation of the test results and an accepted reference value. Bias is the total systematic error as

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The examination of matrices that do not contain claimed analyte, which are potentially cross-reactive, to determine that

they do not produce a measurable response above the claimed LOQ of the method.

3.9 Enzyme-linked immunosorbent assay (ELISA):

An analytical procedure characterized by the recognition and binding of specific antigens by antibodies and signal generation

by an enzyme-substrate reaction

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3.10 Gluten:

A protein fraction from wheat, rye, barley, oats 1 or their crossbred varieties and derivatives thereof, to which some persons 119 are intolerant and that is insoluble in water and 0.5M NaCl (CODEX STAN 118-1979 2.2.1). Throughout this document, the word 120 ‘wheat’ refers to all Triticum species and their crossbreeds, such as triticale, durum wheat, spelt and khorasan wheat, and their 121 hybrids and crossbred varieties such as Triticale. 122 3.11 Incurred Test Material: 123 A material prepared from a food matrix into which a gluten source (e.g. flour) has been incorporated prior to subjecting the 124 matrix to a given food processing operation. 125 3.12 Independent Testing Site: 126 A testing site not owned, operated or controlled by the same entity as the method developer. 127 3.13 Interference Study: 128 The examination of matrices expected to be tested with the method, to demonstrate that they do not interfere with 129 detection of the analyte. 130

1 Oats can be tolerated by most but not all people who are intolerant to gluten. Therefore, the allowance of oats that are not contaminated with wheat, rye or barley in food […] may be determined at the national level [CODEX STAN 118-1979]