Determination of β-Galactooligosaccharides by Liquid Chromatography

Table 6

Calculation of measurement uncertainty.

Sample	GOS content (g/100 g)^a	RSD (iR) (%)	Recovery (%)	RSD(Rec)^∗ (%)^b	𝑢 (%)^c	𝑈 (%)^d
GOS-1A	43.5	2.7	117^f	7.3	7.8	16
GOS-1B	43.7	2.7	120^f	9.4	9.8	20
GOS-2	39.4	3.0	100	1.6	3.4	6.8
GOS-3A	42.4	2.5	110^f	4.8	5.4	11
GOS-3B	54.1	2.1	105^f	2.7	3.4	6.8
GOS-4	26.0	1.8	90.7^f	6.4	6.7	13
GOS-5	66.1	0.7	84.2^f	9.9	9.9	20
GOS-6	43.1	1.4	96.4	1.8	2.3	4.6
Spiked formula	2.63	2.0	102^f	0.69	2.1	4.2
Lactogen 2	2.39	2.0	92.3^f	4.9	5.3	11
Lactogen 2^e	2.58	3.5	97.7	1.2	3.7	7.4

aMedian GOS content as measured.  ^bRSD_(Rec)^∗: the relative standard deviation of the recovery, corrected if the recovery is not 100% and calculated as follows:
SD_(Rec)^∗=((1−recovery)/2)²+SD_(Rec)²   then, RSD_(Rec)^∗=SD_(Rec)^∗/(recovery)×100.
^c𝑢: relative measurement uncertainty expressed in % and calculated as follows:
𝑢=(RSD(iR))²+(RSD_(Rec)^∗)².    
dU: expanded relative measurement uncertainty expressed as % and calculated as 𝑈=2×𝑢.
eResults for this sample obtained using the HPAEC-PAD profiling method. fRecovery is significantly different from 100%.