# Commission Regulation (EC) No 152/2009 of 27 January 2009 laying down the methods of sampling and analysis for the official control of feed (Text with EEA relevance), Division 6: Calculation of results

Extent: E+W+S+N.I.

The amount of tryptophane (X), in g per 100g sample, is calculated as follows:
X=A×B×V1×c×V2×MC×D×V3×10 000×mApeak area of internal standard, calibration standard solution (3.17)
Bpeak area of tryptophan, extract (5.2) or hydrolysate (5.3)
V1 volume in ml (2 ml) of concentrated tryptophan solution (3.15) added to the calibration solution (3.17)
cconcentration in μmol/ml (= 2,5) of concentrated tryptophan solution (3.15) added to calibration solution (3.17)
V2 volume in ml of concentrated internal standard solution (3.16) added at the extraction (5.2) (= 5,0 ml) or to the hydrolysate (5.3) (= 2,0 ml)
Cpeak area of internal standard, extract (5.2) or hydrolysate (5.3)
Dpeak area of tryptophan, calibration standard solution (3.17)
V3 volume in ml (= 2,0 ml) of concentrated internal standard solution (3.16) added to calibration standard solution (3.17)
msample weight in g (corrected to original weight if dried and/or defatted)
Mmolar weight of tryptophan (= 204,23 g/mol)

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Source: https://www.legislation.gov.uk/eur/2009/152/annex/III/division/G/division/6 (the official version)
Page: https://openlegislation.uk/eu-regulation-2009-152/annex-III/division-G/division-6
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.