Review Team (February 2016).pdf

Memo

Monique Steegmans

16001n-MSS-MSS-SLV FOS01 AOAC997.08 Beneo-Orafti, 1 Febr 2016, page 12/18

4. Conclusion.

The method used for this SLV meets the requirements as described in the AOAC SMPR 2014.002

for fructans in Infant Formula and Adult/pediatric Nutritional Formula in which fructan is present in a

concentration ranging from 0.03 to 5.0 g/100g reconstituted final product.

Method performance requirements

SMPR 2014.002

Analytical range

0.03

–

5.0

Limit of quantitation

(LOQ)

≤0.03

Repeatability (RSDr)

≤6%

Recovery

90 to 110% of mean

spiked recovery over

the range of the assay

Reproducibility

(RSD

)

≤12%

The

precision,

observed during this SLV following FOS-01 meets the repeatability as proposed by

the workgroup, as the average RDSr is

≤

6%. Like prescribed by the SLV the samples from the Kit,

fortified with fructan, were analyzed in double on 6 different days by different operators.

The

accuracy

was performed by spiking the Test Materials Kit samples by 3 different pure fructan

products of different origin (sugar and chicory) and DP range. The spiking/recovery ranges from

96.9 to 107.1% with a mean of 100.3%, which is very well meeting the proposed requirement of

90-110%. The very low concentrations (spike level 0.05 near to LOQ) are included during this

spiking test and even these meet the proposed range.

The precision and accuracy are part of the performance of the proposed method, and

as the Test Materials Kit contains fortified samples with unknown amounts, the recovery of those

should also be calculated. Comparing the spiked amounts of fructan in the Test Materials Kit with

the reported fructan results of each proposed method provides information about of

the

performance

of the FOS method proposed. This can’t be done by the author bu

t is still a task to

be done for every method proposed for FOS determination.

The method as proposed corrects for the glucose part but in contrast to the methods that treat the

samples by borohydride (Cuany et al: Journal of AOAC int. Vol93, N°1, 2010) to get rid of the

reducing sugars, this method FOS-01 does not have to correct for the missing part of the F

chains. Consequently the influence of the factor is smaller in comparison with the methods based

on the Cuany

method. In case the type of inulin that is added can’t be identified, a mean factor can

be applied which influences the final fructan content not significantly. The applied factor for

oligofructose derived from chicory or sugar is also different as the ratio fructose to glucose coming

from the fructans is very different.

HPAEC has the disadvantage that every 6 injections samples have to be bracketed with standards.

Fos-01 (February 2016)

FOR ERP USE ONLY

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