NF EN ISO 13904
Animal feeding stuffs - Determination of tryptophan content
ISO 13904:2016 specifies a method for determination of the total and free tryptophan (Trp) content in feeding stuffs (e.g. complete and complementary feeds, supplementary feeds, raw materials, ingredients, and concentrates) and determination of free tryptophan in commercial pure substances and premixtures containing more than 2 % of tryptophan.It does not distinguish between D- and L-forms.
ISO 13904:2016 specifies a method for determination of the total and free tryptophan (Trp) content in feeding stuffs (e.g. complete and complementary feeds, supplementary feeds, raw materials, ingredients, and concentrates) and determination of free tryptophan in commercial pure substances and premixtures containing more than 2 % of tryptophan.
It does not distinguish between D- and L-forms.
ISO 13904:2005 describes the determination of the total and free tryptophan in feeding stuffs (e.g. complete and complementary feeds, supplementary feeds, raw materials, ingredients, premixtures and concentrates. It does not distinguish between D- and L-forms.
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1 Domaine d'application
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2 Principe
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3 Réactifs et matériaux
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4 Appareillage
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5 Mode opératoire
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6 Calcul des résultats
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7 Fidélité
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8 Rapport d'essai
- Annexe A Résultats d'un essai interlaboratoires
- Annexe B Observations sur la méthode
- Annexe C Préparation des échantillons: Exemples portant sur des analyses dans des produits purs et des prémélanges
- Annexe D Résultats d'un essai interlaboratoires portant sur le tryptophane dans les produits purs et les prémélanges contenant plus de 2 pourcent de tryptophane
- Bibliographie
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