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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:
Abbott
Summary of Method:
A two part analysis with Part 1 is the qualitative classification of the fructan present in the sample, if not
already known. This classification is based on rules related to presence/absence of GF3 (Nystose) and GF4
(fructofuranosylnystose), specifically, and higher oligomers, generally. It groups the fructans into one of
three DP ranges and allows selection of an appropriate commodity factor for converting fructose content
to total fructan content. Part 2 is the quantitative determination of total fructan in the sample. The sample
to be analyzed is weighed and diluted with lab water, as appropriate. Part 1 of the analysis is then
performed.
Part 2 can be run in parallel, whereby an aliquot of the diluted product is 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. Excess
borohydride is neutralized by the addition of acetic acid. An aliquot of internal standard (glucoheptose) and
an aliquot of 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 fructose, adjusted by a commodity factor (Part 1).
Method Scope/Applicability:
Infant Formula and Adult/Pediatric Formulas and ingredient commodities
General comments about the method:
Time consuming in the qualitative work needed upfront before you can start analysis of an unknown
sample, so the conversion factor can be determined. It uses HPAEC-PAD which is less common in labs than
GC-FID and can be interfered with by maltodextrans which are common in dairy preps requiring further
enzyme steps which are described.
Method Clarity:
Clearly written method although very complex approach.
Method Safety Concerns:
Standard laboratory safety.
#4
FOS-04 Review Forms