AOAC ISPAM Stakeholder Panel Meeting Book 9-24-17

In addition, developers will also be required to show ruggedness, inclusivity, exclusivity as 168 described in the references (1,2). 169 170 We anticipate procurement of materials for spiking here at General Mills for gluten-free oat 171 flour and also most contaminant grains. We hope to develop a series of test materials which 172 will be made available to all kit developers to evaluate proposed kit response. 173 We should note here that in the past, it was common to use purified protein materials as spiking 174 agents to assess the recovery of kits. Previous OMA methods had used the PWG gliadin 175 standard as spiking material, with good success. In this project, it will be difficult to obtain 176 similar materials for hordein and secalin, but in this case, we feel it appropriate to use 177 unextracted grains as spiking materials. We feel this recovery experiment should be a 178 demonstration of both the antibody response and the extraction efficiency – it is a validation of 179 the entire kit, not just the antibodies. As such, it is better to demonstrate the ability of the 180 method to extract and detect the proteins from grain materials in their native and cooked 181 states. 182 183 Gluten-Free Oat Flour 184 We have obtained very low GF oat flour for spiking materials by mechanically cleaning oats and 185 selecting the fraction expected to be lowest in gluten. For spiking purposes, we look for flour 186 lots with anobserved analytical mean < 1 ppm gluten as tested by the R5 ELISA method, 18 187 replicates at 5 g test portion. Flour at this level is deemed low enough to be used in spiking 188 experiments. 189 190 Contaminant Grains 191 As we have encountered in previous work, the decision on what contaminant grains to use in 192 spiking studies is controversial. The age-old question is whether or not to use a single cultivar, 193 or use a blend of common cultivars which are widely planted in the region. We have obtained 194 several common rye and barley cultivars currently planted in North American oat regions for 195 study. At the guidance of the Working Group, we are willing to blend these cultivars, or use 196 them unblended to make spiking materials. See Appendix A for a list of cultivars and how they 197 were chosen. 198 199 For wheat spiking material, we were anticipating using the MoniQA wheat gluten flour material, 200 but as yet, that has not been made available to us. If time is critical, we would be willing to 201 source common wheat cultivars from our wheat breeder contacts and perform similar 202 operations to develop a blend of wheats to use as spiking materials. 203 204 Characterizing the Contaminant Grains 205 We anticipate grinding each cultivar independently, then weighing together appropriate masses 206 of flour to make the spiking blend. After the composite blend is made, it will need to be tested 207 for gluten content. The gluten estimate of the spiked material will be necessary to calculate 208 recovery. We have several ideas on how to do this. We hesitate to refer to this step as a 209 “reference” method in fear that whatever the Working Group decides as the best way to 210 accomplish this will enshrine this method as the best or only way to do this type of 211 characterization. We don’t want to establish a precedent on the ideal method, but would only 212 use this as a way of calculating recovery. 213