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Multi Laboratory Test – AOAC First Action Method 2012.22 Ascorbic Acid (Vitamin C) in Infant Formula and
Adult/Pediatric Nutritionals.
RDLS-RD150006
E. Campos Giménez (NRC, Lausanne)
Page 7
CONFIDENTIAL
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This document may not be reproduced or disclosed to third parties without prior authorisation.
INSTRUCTIONS TO PARTICIPANTS
Part 1: Method set up and qualification of participants
Practice
Samples
Receipt
All participant laboratories received two practice samples. The “SPIFAN Practice
Samples Receipt Form” (see Annex E) was to be filled and sent back to the
Study Director.
Before undertaking the analysis, were instructed to keep the samples at room
temperature, away from direct sunlight. Once open, the containers were to be
kept at 4 °C in tightly closed containers for the duration of the study.
Analysis
The laboratories set up the method described in Annex B. It was highlighted
to closely follow the method described in this document, since small
adaptations might have been included with respect to the previously
published method.
The laboratories were asked to analyze each of the two practice samples in
duplicate (two extractions from each reconstituted sample). Any deviation,
such as necessity to substitute reagents, columns, apparatus or instruments,
was to be recorded and reported.
Timeline
The results on the two practice samples were to be sent to the Study Director
within 6 weeks from sample reception.
Reporting
An electronic template was provided for data reporting (see Annex F).
Participating laboratories were required to report peak areas in the standard
curve, as well as in the sample extracts. Furthermore, detailed information on
the different masses and volumes used during sample preparation as
indicated in the method, as well as raw data (chromatograms of standards
and samples) were requested.
Laboratories were asked to report final results in mg ascorbic acid/100 g of
“reconstituted powder” for powder samples or “as is” for liquid products, with
3 significant figures.
Laboratory
Qualification
After review by the Study Director, results within a range of expected levels
identified the laboratories which had the capability to run the analysis
successfully. They were thus qualified for the second part of the study. The
laboratories received notification within 2 weeks from data reporting.
AOAC OMB Meeting Book
341