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Dual Lab Validation of a Method for the Determination of Fructans in Infant
Formula & Adult Nutritionals /
25 Jul 2016
18
model) using two different columns (same column type, different batch number), results are shown
in Table 5.
The SMPR [2] requires that the RSD(r) should be less than or equal to 6%. In all cases the achieved
RSD(r) was less than 3%, thus the method meets the requirements of the SMPR for RSD(r). The
RSD(iR) was also less than 3% in all cases suggesting that the method should be able to achieve an
RSD(R) of less than 12% during multi lab testing (as required in the SMPR).
Table 5: Analyses of Fructan-Containing Samples Under Intermediate Reproducibility Conditions
Nestle
Code
Sample Description
n
Mean Conc.
(g/100g)
RSD(r)
(%)
RSD(iR)
(%)
Target
RSD(r)
(%)
Meets
Target
(Y/N)
KBI‐00020 Child Formula Powder
6×2
0.273
0.78
1.1
≤ 6
Y
KBI‐00035
Toddler Formula
Powder Milk Based
6×2
0.210
1.2
2.4
≤ 6
Y
KBI‐00044
Infant Formula
Powder Milk Based
7×2
0.280
2.5
3.0
≤ 6
Y
KBI‐00046 Child Formula Powder
6×2
0.275
1.2
1.1
≤ 6
Y
KBI‐00053
Infant Formula
Powder
FOS/GOS Based
6×2
0.033
a
0.9
2.5
≤ 6
Y
KBI‐00051
Adult Nutritional RTF
High Fat
6×2
0.481
1.8
1.6
≤ 6
Y
Ref 40C
Milk Powder with
Prebiotics
6×2
2.85
b
1.1
1.8
≤ 6
Y
Ref 64A
Infant Formula
24×2
0.390
a,b
3.2
4.2
≤ 6
Y
a
Although it is recommended to analyse samples with fructan content below 0.15 g/100g (on a RTF basis) using the procedure including
a blank subtraction, this had not been defined at the time of the precision experiment, thus the precision data on these samples do
not include the blank subtraction step. All concentrations are in g/100g of ready to feed product (either reconstituted powders or the
liquid products directly) except
b
in which the concentration is reported in g/100g of the non‐reconstituted powder.
3.3. Method Accuracy
Six different blank matrices were spiked at three levels with three different fructan ingredients (as
described in Table 4). Recoveries were calculated by comparing the spiked amount vs the measured
amount (Table 6). At the 2 higher spiking levels recoveries were in general very good (92 – 104 %)
with one exception, the adult nutritional RTF high protein sample, for which the average recovery
was only 86 %. At the lowest spike level (0.03 g/100g) which is equivalent to the desired LoQ
specified in the SMPR [2], the recoveries are less good, varying from 101 – 151 %, with three
matrices achieving the SMPR requirements (recoveries between 101 – 105 %) and three matrices
being outside the requirements (recoveries between 114 – 151%). Because the spike level is very
low, a small amount of interference can have a significant impact on the recovery. In order to
correct for this interference the method was adapted for samples containing very low fructan levels
VALIDATION REPORT
FOR ERP USE ONLY
DO NOT DISTRIBUTE