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AOAC First Action Method 2016.02 (Biotin) MLT Report
Page 4 of 16
2.2. Multi laboratory testing by qualified participants
The qualified laboratories were then asked to analyse the MLT samples on two different days following a
carefully designed protocol provided. The results were submitted to the study director for evaluation.
Unless otherwise specified in the protocol, all powdered samples were analysed on a reconstituted basis,
using 25 grams of sample into 225 grams with water, as stated in the attached method. An electronic
template was provided for data reporting including system suitability, linearity, peak areas of the standard
curve as well as of the sample extracts. Furthermore, detailed information on the different weights and
volumes used during sample preparation as indicated in the method, as well as raw data (chromatograms
of standards and samples) were requested.
Laboratories are asked to report final biotin and biocytin results in
µ
g/100 g to two decimal places.
2.3. Statistical evaluation
After data collection, outliers were detected using Cochran and Grubbs tests. The number and coded
identity of statistical outlier laboratories is included in the final report. Average biotin concentrations,
standard deviations of repeatability (S
r
) and relative standard deviations of repeatability (RSD
r
) were
estimated from blind duplicates in MLT samples. The blind coded duplicates were analysed on the same
day. Standard deviations of reproducibility (S
R
), relative standard deviations of reproducibility (RSD
R
), and
HorRat values (RSD
R
/predicted RSD
R
) were also determined.
3. MATERIALS AND METHODS
3.1. AOAC SPIFAN Matrices
The study was carried out using SPIFAN matrices, which represent most of the products in the scope of the
project (Infant Formula and Adult Nutritionals made from any combination of milk, soy, rice, whey,
hydrolysed protein, starch and amino acids, with and without intact protein). Fourteen different product
types were provided to each laboratory which includes two practice samples and 12 samples for multi
laboratory testing over two separate days. Two split samples of each matrix were included in the package
as blind coded duplicates to analyse on the same day. Please refer to Table 1 for sample details.
Homogeneity assessment of AOAC SPIFAN product matrices were performed by analysing several active
nutritional ingredients. The testing was performed by
Covance Laboratories Inc. in one of their facilities.
The homogeneity report was provided to the study director before commencing the MLT programme.
Table 1: AOAC SPIFAN Matrices
Samples
Product Description
Batch / Lot #
Blind Duplicate Codes
Practice 1
Infant Formula Powder Partially Hydrolysed Soy Based
410457651Z
SWUO667
SWUO667
Practice 2
Infant Formula Powder FOS/GOS Based
50350017W1
URTF231
URTF231
MLT - 1
Infant Formula Powder Partially Hydrolysed Milk Based
410057652Z
KDOX966
ATAN351
MLT - 2
Infant Elemental Powder
00795RF
ECHL425
UOPM297
MLT - 3
Infant Formula RTF Milk Based
EV4H2R
XKIP216
HYJU890
MLT - 4
Adult Nutritional RTF High Fat
00729RF00
DYLB360
ZMQM883
MLT - 5
Infant Formula Powder Milk Based
4044755861
NSRB999
JSDT587
MLT - 6
Infant Formula Powder Soy Based
E10NWZC
TJHR217
OACN211
MLT - 7
NIST SRM 1849a
CLC10-b
KGSZ273
LTCT316
MLT - 8
Adult Nutritional Powder Low Fat
00859RF00
LYNY751
PZGP859
MLT - 9
Child Formula Powder
00866RF00
RQXQ518
GVPE615
MLT - 10
Toddler Formula Powder Milk-Based
4052755861
EFXN778
BFA0941
MLT - 11
Infant Formula Powder Milk Based
K16NTAV
CULF358
GBZC169
MLT - 12
Adult Nutritional RTF High Protein
00730RF00
FPTE312
DOMY545
2016.02 (FEBRUARY 2017) BIO-02 MLT REPORT
FOR ERP USE ONLY
DO NOT DISTRIBUTE