Fermentation-derived L-valine using Corynebacterium glutamicum CCTCC 20232578

The European Food Safety Authority (EFSA) has recently made recommendations regarding the identification of L-valine, a feed additive intended for use in all animal species, in various products such as the feed additive itself, premixtures, compound feed, and water.

The EFSA's recommendations come in response to an authorization application for L-valine produced by fermentation with Corynebacterium glutamicum CCTCC 20232578, under the categories "nutritional additives" and "amino acids, their salts and analogues."

Initially, an applicant proposed a method for determining L-valine based on ion exchange chromatography coupled to post-column derivatisation and optical detection (IEC-VIS). However, this method has been criticized for its inability to differentiate between enantiomers of valine and for not distinguishing between the salts of amino acids.

To address these concerns, the EFSA has recommended the use of the "L-valine monograph" of the Food Chemical Codex monograph for the identification of L-valine in the feed additive. This method was not included in the applicant's proposed method.

In addition, the EFSA has recommended two alternative methods for determining valine in the feed additive, premixtures, and water. These methods are based on ion exchange chromatography coupled to optical detection (IEC-VIS/FLD), as outlined in the EN ISO 17180 and the European Union (EU) method (or equivalent EN ISO 13903).

The reported relative standard deviation for repeatability (RSDr) for the determination of total valine in feedingstuffs using the applicant's method ranges from 1.7 to 3.8 %, while the relative standard deviation for reproducibility (RSDR) ranges from 8.8 to 16.1 %. The feed additive L-valine is intended to be mixed into premixtures, incorporated through complementary feed, added directly to compound feed or water for drinking.

The minimum purity of the feed additive L-valine is 94%. The EFSA's recommendations aim to ensure the accurate and reliable identification and determination of L-valine in various animal feed products, contributing to the overall safety and efficacy of the feed additive.