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

It is not anticipated that this procedure will be available commercially, which is why suggested conversion factors are provided. ANNEX B : In the example provided to determine the gluten content in a barley flour, the conversion factor used 0.75 is not the conversion factor of the above list for barley (0.78). As a consequence the rest of calculations seem to be wrong. Fixed ANNEX C : Concerning the matrix related to cereal grains in the hydrolyzed section, may be it is preferable to use soy, or rice drinks instead of soy or rice milk. Changed to soy and rice beverages ANNEX C : The text of annex 3 is too small That was simply a function of how it was displayed for review – it will be adjusted in the final document ANNEX D : DF, SS, MS, VC abbreviations should be defined. Added below the table ANNEX D : Page 28 The case with "mean" is weird in the second table Edited The following are VIM4 Second Committee Draft Definitions, as compared to the definitions used in the gluten quantitative draft document:

Current Definition

VIM4 Second Committee Draft Definition

3.2 Bias: Difference between the expectation of the test results and an accepted reference value. Bias is the total systematic error as contrasted to random error. There may be one or more systematic error components contributing to the bias.

measurement bias bias estimate of a systematic error NOTE 1 Measurement bias differs from bias in mathematical statistics. Measurement bias should be accompanied with a stated uncertainty which can be negligible for some purposes. NOTE 2 Sometimes measurement bias is incorporated in a measurement model as a correction for an estimated systematic error.