AOAC 133rd Annual Meeting - Final Program

Poster Abstracts | Tuesday

properties, prebiotic function and immune modulation are, among other, demonstrated health benefits that are related to HMO. 2’-fucosyllactose (2’-FL) is one of the most abundant HMO and has been the subject of extensive studies regarding its presence in human milk and its biological activity. In the ongoing effort to produce infant formulas that provide to newborns nutri- tional and health benefits comparable to those of human milk, their fortification with HMO, and particularly with 2’-FL, was suggested. The presented information will summarize the devel- opment, validation and related statistical results of a method for 2’-FL quantification in ingredients, premixes, infant formulas and ready-to-feed formulas. Presenter: Ioannis Vrasidas, Eurofins Food, Feed & Water Testing Netherlands, Heerenveen, Netherlands, Email: yannisvrasidas@eurofins.com P-T-069 Navya Jonnalagadda , Ryan Malone , Trilogy Analytical Laboratory, Hyderabad, India; Subramanian Sankaran , Trilogy Analytical Laboratory, Mumbai, India; Shivani Desai , R-Biopharm Neugen Pvt Ltd, Hyderabad, India Influence of the Number of Participants in a Consensus- Based Proficiency Testing Round on the Uncertainty of Assigned Value and Performance Assessment Score When an assigned value (AV) for proficiency testing is derived by the consensus method, a common method to calculate uncertainty of the AV is by applying the equation, 1.25 times the standard deviation of AV by the square root of the number of participants. Uncertainty of the AV should be less than 30% of the standard deviation for proficiency assessment. If this criterion is met then the uncertainty is negligible and z-score is applicable for performance assessment, if not met the uncertainty is not negligible and should be considered during performance assessment by utilizing z’ scores. This study evaluated the effect that the number of participants in a round has on the calculation of uncertainty with above equa- tion, the influence of number of participants on the criteria for uncertainty negligibility and the selection of z -score or z’ score.

Data supports that minimally 18 participants are needed to accurately satisfy the acceptance of uncertainty criteria, stated in ISO 13528:2015. Without minimally 18 participants the uncertainty of the AV calculated from the formula mentioned cannot be adequately estimated. This renders the criteria for uncertainty negligibility ineffective, compelling z’ score usage or alternative methods of uncertainty estimation. Presenter: Navya Jonnalagadda, Trilogy Analytical Laboratory, Hyderabad, India, Email: navya@trilogylab.in Hirao , House Foods Group Inc., Yotsukaido, Japan; Michie Hashimoto , Hirotaka Unno , Yuuki Yonekawa , Ricoh Co., Ltd, Kawasaki, Japan; Reiko Adachi , National Institute of Health Sciences, Kawasaki, Japan Novel DNA Reference Material by Bioprinting IX: Application for Quality Control of the Qualitative Real- Time PCR Method for Food Allergens We have reported the sensitive qualitative real-time PCR methods for food allergens in the previous annual meeting. The methods are designed to avoid false positives due to trace contamination while keeping the sensitivity. Based on this, we set the cutoff for determination of positive threshold cycle (Ct) using the reference-plasmid containing the PCR target sequence. The cutoff copy number of the r-plasmid was set at 50 copies/reac- tion according to Abs 260 . The cutoff Ct analyzed in every PCR run effectively minimize the differences between PCR runs or instru- ments. The bioprinting technology, injecting a desirable DNA sequence introduced in a yeast cell onto a tube, can control copy number of the introduced sequence. We first tried to use it as a cutoff instead of the conventional r-plasmid. As a result, novel DNA reference-material prepared by bioprinting worked properly as a cutoff on LightCycler 96. The observed RSDs of copy numbers of the DNA r-materials were smaller than those of the r-plasmid. But significant bias of copy numbers between PCR instruments were observed in the DNA r-materials compared to the control r-plasmid. Therefore, we concluded it is difficult to use the DNA r-material as a cutoff. Next, we tried to use the bioprint- ing for quality control of the r-plasmid. Our simulation results showed the small RSDs of copy numbers of the DNA r-materials would be useful for QC to reduce lot-to-lot variation of copy number of the r-plasmid within a PCR instrument. Presenter: Satoshi Watanabe, House Foods Group Inc., Yotsukaido, Japan, Email: s-watanabe@housefoods.co.jp P-T-072 Kazumi Kitta , Reona Takabatake , National Agriculture and Food Research Organization, Tsukuba, Japan; Hirotaka Unno , Michie Hashimoto , Ricoh Co., Ltd, Kawasaki, Japan; Ian Riztyan , Mari Onishi , Satoshi Futo , FASMAC Co. Ltd, Atsugi, Japan Novel DNA Reference Material by Bioprinting I: Its Significance and Applications Polymerase chain reaction (PCR) has been extensively applied to molecular diagnostics and detections as a gold standard technique. The PCR technique has highly specific and sensitive P-T-071 Satoshi Watanabe , Akiko Miyazaki , Takashi

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