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© 2013 AOAC INTERNATIONAL
(
e
)
Identification
.—Identify the ascorbic acid peak in the
chromatograms of the sample solutions by comparison with the
retention time and UV spectrum of the corresponding peak in the
standard solution.
H. Calculations
Calculate the concentration of vitamin C, in mg ascorbic
acid/100 g expressed in product “as is” for RTF (ready-to-feed)
products or as “reconstituted powder” for powder samples, as
follows:
1000 x V x m x S
100 x V x V x )I-A( C
2
3
1
=
where A = response (height or area) of the ascorbic acid peak
obtained for the sample solution, m = weight of the test portion in
g (2.0 g), V
1
= volume of the test solution (volume used to dissolve
the test portion) in mL (10 mL), V
2
= volume used in the sample
dilution (1.0 mL), and V
3
= volume of the final sample dilution
(10 mL).
Note
: If results expressed in powder sample are needed, use the
reconstitution rate to calculate (c × 225/25).
References:
J. AOAC Int . 96 , 1065(2013)DOI: 10.5740/jaoacint.13-141
AOAC SMPR 2012.012
J. AOAC Int . 96 , 491(2013)DOI: 10.5740/jaoac.int.SMPR2012.012
Corrected November 2013 [to correct concentrations of mobile
phase in
D
(
a
),
D
(
d
), and
G
(
a
)(6)]
AOAC OMB Meeting Book
306