L-valine

In the current application authorisation is sought under Article 4(1) for L-valine produced by Corynebacterium glutamicum KCCM80058, under the category/functional group 3(c) 'nutritional additives'/'amino acids, their salts and analogues', according to Annex I of Regulation (EC) No 1831/2003. Authorisation is sought for all animal species. The feed additive is intended to be mixed either in premixtures or added directly to feedingstuffs or water. The Applicant proposed no minimum or maximum L-valine concentrations in feedingstuffs.

For the determination of L-valine in feed additive, premixtures and feedingstuffs the Applicant submitted the Community method (Commission Regulation (EC) No 152/2009) further ringtrial validated by CEN, resulting in the EN ISO 13903:2005 standard method. The following performance characteristics were reported for the determination of total valine in premixtures and feedingstuffs: - a relative standard deviation for repeatability ranging from 1.7 to 3.8 %; and - a relative standard deviation for reproducibility ranging from 8.8 to 16%.

Even though no performance characteristics are available for the determination of valine in feed additive, several NRLs consider the Community method suitable for official control, as already recommended by the EURL in earlier reports (FAD-2007-0015; FAD-2012-0023).

Furthermore, the EURL identified the "L-valine monograph" of the Food Chemical Codex (FCC), where identification is based on infrared absorption in combination with the analysis of the optical rotation, while quantification is based on titration.

Based on the technical evidence available, the EURL recommends for official control (i) the Food Chemical Codex for the determination of L-valine in the feed additive and (ii) the ringtrial validated Community method (EN ISO 13903:2005), based on ion exchange chromatography coupled with post-column derivatisation and spectrophotometric detection to determine valine in feed additive, premixtures and feedingstuffs.

The EURL cannot evaluate nor recommend any method for official control to determine Lvaline in water, as the Applicant did not provide any experimental data or analytical methods. 

Further testing or validation of the methods to be performed through the consortium of National Reference Laboratories as specified by Article 10 (Commission Regulation (EC) No 378/2005) is not considered necessary.

Recommended Method

as of:

- Commission Implementing Regulation (EU) 2025/2183

For the identification of L-valine in the feed additive:

• Food Chemical Codex ‘L-valine monograph’

For the determination of valine in the feed additive:

• Ion-exchange chromatography coupled with post-column derivatisation and optical detection (IEC-VIS)

For the determination of valine in premixtures and compound feed:

• Ion-exchange chromatography coupled with post-column derivatisation and optical detection (IEC-VIS), Commission Regulation (EC) No 152/2009