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FOR EXPERT REVIEW PANEL USE ONLY
NOT FOR DISTRIBUTION
1
Expert Review Panel for Infant Formula and Adult Nutrition
Evaluation of Method FOS-04
Title:
Determination of Fructans in Infant and Adult/Pediatric Nutritional Formula as well as ingredient
commodities
Author:
Haselberger (Abbott)
Summary of Method:
A two part analysis is performed. Part 1 is the qualitative determination of the type of fructan present in
the sample. Part 2 is the quantitative determination of fructan in the sample. The sample to be analyzed is
weighed and diluted with lab water. In part 1 the type of fructan is determined using certain rules based on
retention time. In part 2 samples are treated with sucrase to hydrolyze any sucrose present. Glucose and
fructose released by the enzymatic hydrolysis, as well as inherent glucose and fructose, are then reduced
to sugar alcohols by the addition of sodium borohydride. Internal standard (glucoheptose) and fructanase
are added to the sample solution. After the fructanase hydrolysis is completed, the samples are analyzed
for fructose on HPAEC-PAD instrumentation. The total fructan content is calculated from the peak areas,
adjusted by a commodity factor (CF, determined by part 1).
Method Scope/Applicability:
The method is applicable for Infant formula, adult / pediatric nutritional formula, and commodity
ingredients.
General comments about the method:
•
Based on the principle of AOAC 999.03: glucose and fructose (also from sugar) are reduced to sugar
alcohols; then fructans are hydrolyzed to fructose, which is subsequently analyzed
•
As in Cuany
et al.
, HPAEC-PAD is used for fructose analysis instead of the PAHBAH spectro-
photometric method
•
Using a borate trap reduces sample preparation
•
The approach is to solve the problem of reduced precision of certain fructan types (high Fm type
fructans with low chain length) by first determining the type of fructan that is added
Method Clarity:
•
In general clearly written, including supporting tables and figures
•
Extensive examples explaining how to determine the type of fructan
•
Gradient in part 1 is now clarified
•
Calculation of Commodity Factors is now included
•
Calculation of fructan content was adapted to prevent double inclusion of Commodity Factor
Pros/Strengths:
#1
FOS-04 Review Forms