2018 Sugar ERP - Method Review Book

AOAC SMPR ERPs - 2018 METHOD REVIEW FORM

Submission ID

4099965788519339504

Submission Date

2018-08-13 14:09:38

Name

John Szpylka

E-mail

john.szpylka@mxns.com

Organization

Merieux NutriSciences

Title of Method

Single Lab Validation of Megazyme's Fructan Assay Kit (K-FRUC) Method for the Determination of Fructan (Inulin, FOS, Levan and Branched Fructan) in Animal Food (Animal Feed, Pet Food, and Ingredients)

AOAC Candidate Method Number (e.g. ALN-01)

SUG-002

Applicable SMPR

2018.002

I. Summary of the Method

The forms of fructans listed in SMPR are extracted from pet foods, feeds, and ingredients into boiling water. Sucrose, starches, and maltodextrin are concurrently enzymatically hydrolyzed to glucose and fructose. All reducing sugars are then converted to sugar alcohols, thus removing them as potential interferences. The method states native fructans and non-reducung FOS are not affected by these reactions. The SMPR-listed fructans are hydrolyzed to fructose and glucose using a mixture of three enzymes to cover the different possible fructan internal sugar linkages. Quantitation of the total amount of reducing sugars (fructan-derived fructose and glucose) is performed using the PAHBAH reducing sugar method. A single point calibration of absorbance /54.5 ug fructose is used. The total dietary fructan amount of inulin, FOS, levan, and branched fructan is measured by this method. The method removed interferences of starches, sucrose, and other reducing sugars.

II. Review of the Method Only 1. Does the applicability of the method support the applicability of the SMPR? If not, please explain what is missing. 2. Does the analytical technique(s) used in the method meet the SMPR? If not, please specify how it differs from what is stated in the SMPR. 3. Are the definitions specified in the SMPR used and applied appropriately in the method? If no, please indicate how the terms are used.

The analytical technique does measure the total amount of ditetary fructans.

All definitions are used correctly except for reproducibility. The reported RSDR study was performed on 4 separate occasions by 2 independent analysts. While these results should remain in the report as an intermediate precision study, a broader number of variables (different locations, equipment, reagents, and analysts) needs to be performed to fully estimate method reproducibility (RSDR).