AOAC OMB Final Action Recommendation (December 2019)-2016.14

FOR EXPERT REVIEW PANEL USE ONLY NOT FOR DISTRIBUTION

Expert Review Panel for Infant Formula and Adult Nutrition Evaluation of Method ____AOAC 2016.14 (Fos 03)_______________ Title: Determination of Fructans in Infant Formula and Adult Nutritionals by Anion-Exchange Chromatography with Pulsed Amperometric Detection after Enzymatic Treatment Authors: Sean Austin, (NR-NIFSAS) and Véronique Spichtig (NRNIFSAS), Kommer Brunt (Rotating Disc BV, Haren, The Netherlands), Jeroen van Soest and Peter Sanders (Eurofins Carbohydrate Competence Centre, Heerenveen, The Netherlands) Reviewer Name: Reviewer 1 Summary of Method: Samples are reconstituted in water (if required) and further diluted until the concentration of fructan in solution is such that after hydrolysis the fructose and glucose concentration is within the range covered by the standard curve. The diluted sample is treated with a mixture of sucrase and α-glucanases to hydrolyze sucrose and alpha-glucooligosaccharides to their constituent monosaccharides. The sample is passed through a SPE column packed with graphitized carbon. Salts and monosaccharides pass through and are washed away, while the fructans are retained. Fructans are released from the column using an acetonitrile solution. The released fructans are hydrolyzed with an inulinase mixture, and the released glucose and fructose are analyzed by high performance anion- exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The fructan content is calculated by summing the glucose and 0.9 × the fructose content measured. In some matrices containing low amounts of fructans, a blank correction may be necessary and can be applied. Method Scope/Applicability: Applicable to the analysis of fructo-oligosaccharides and inulin’s at all levels above the detection limit in infant formula and adult nutritionals. General comments about the method: Excellent method. Great to see such progress after many years of struggling with the assay of these analytes. A real pat on the back goes to the team members who made this happen. Great work. Method Clarity: Excellent and easy to follow. (although I think the method is well written and clear, it is evident from some of the feedback from participants that the old saying still holds true: Analysts would rather use your toothbrush than to use the method you are sharing with them.) Method Safety Concerns: Properly and adequately addressed. Pros/Strengths: • Well written and clear. • Quantitates polyfructoses without regard to source or processing and arrives at the accurate result. • Excellent precision for such tough challenge. Even though the SMPR was not quite met for a couple of samples, this method will stand up to the challenges of the needs of various users.

• Exceeds the performance of anything done here to for on these analytes. • Adding the sucrase performance criteria is a great way to handle an issue.

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