AOAC SPSFAM ERP for SELECTED FOOD ALLERGENS

4. Based on the supporting information, what are the pros/strengths of the method?

If additional details on how the supporting information were generated are provided, it may be that the method fits a majority (but not all) of the performance requirements. The results generated from the in house incurred/spiked food calibration curve appear to be quite good with respect to repeatability. In the tested food matrices, the method also appears to have the specificity required for a food allergen method. As discussed elsewhere in this review, the reporting units for the method do not match those in the SMPR, and this issue must be addressed as it affects whether the method meets many of the performance requirements. The quantification strategy that was applied and how an end user would quantify results needs extensive clarification (as discussed in previous questions). If the quantification is to be conducted with a calibration curve derived from the incurred/spiked foods produced by the method developer, then the assessment of method performance must be conducted on other relevant samples. The authors state (on p. 18) that, “For the final method, two proteins, two unique peptides for each protein and two MRM transitions for each peptide, i.e. total of eight MRM transitions, were used for each allergen commodity to ensure identification confidence (Table 2).” However, this statement does not hold true in several cases: Egg: - The peptides (EggYolk.Protein_2.Peptide_A and EggYolk.Protein_2.Peptide_B) listed in Table 1 as targets for Gal d 5, serum albumin, are not present in this protein. Instead, these peptides are from Vitellogenin-2. The other set of peptides from egg yolk are correctly stated to be from Gal d 6, Vitellogenin-1, which is another isoform of the protein.

5. Based on the supporting information, what are the cons/weaknesses of the method?

6. Any general comments about the method?