Determinationof Fructans in Infant FormulaandAdult
Nutritionals
High-PerformanceAnion-ExchangeChromatographywithPulsed
AmperometricDetection
SeanAustinandDenisCuany
NestléResearchCentre, Vers-Chez-Les-Blanc, POBox44, CH-1000 Lausanne26, Switzerland
Notes :
1.
Themethoddescribedanddatapresentedarealreadypublished in Cuany,D., et.al.
(2010)
J. AOAC Int
.
93(1):
202-212
2.
Weare currentlyworkingonan improvement of thismethodbut it isnot yet ready
for submission. Mainchangeswill be:-
a.
Different column (avoidsneed for post-columnadditionofNaOH).
b.
Additionof an internal standard.
c.
Removal of thedrying stepafter SPE .
d.
Determinationof 4analytes (glucose, fructose, sorbitol andmannitol) to
avoid theneed for correction factors.
e.
Useofmulti-point calibration.
A.
ApplicabilityStatement
Thismethod is suitable for thedeterminationof fructans in infant formula (hasnot yet been
validatedonadult nutritional products)
B.
Principle
Fructans areextracted from the samplewithhotwater. Analiquot of theextract is treated
witha sucrase tohydrolyse sucrose intoglucoseand fructose. Concurrently, starchand
maltooligosaccharides arehydrolysed toglucoseby combinedactionof highlypurified
amylase, pullulanaseandmaltase. Reducing sugarsare then reduced to the corresponding
sugar alcoholsby treatmentwithalkalineborohydrideand themixture cleanedupby SPEon
agraphitized carbon column, thus removingallmonosaccharides andborate salts. Fructans
are recovered from the columnbyelutionwithacetonitrile/trifluoroacetic acidanddried.
Thedried fructans are redissolvedand treatedwithapurified fructanase (endoandexo-
FOS-03
FORWORKINGGROUP/ERPUSEONLY
DONOTDISTRIBUTE
