EU reviews new L-lysine additives for animal feed under stricter testing rules
A new authorisation request has been submitted for three forms of L-lysine used in animal feed. The application covers L-lysine monohydrochloride, concentrated liquid L-lysine, and L-lysine produced via fermentation with specific Corynebacterium glutamicum strains. These additives are intended for use across all animal species as both nutritional and sensory supplements.
The European Commission, supported by national reference laboratories, oversees the validation of testing methods. Meanwhile, the European Reference Laboratory (EURL) has provided recommendations on the most suitable analytical approaches for different applications.
The authorisation is being sought under Article 4(1) of Regulation (EC) No 1831/2003. The three additives—L-lysine monohydrochloride, liquid L-lysine, and fermentation-derived L-lysine—must contain minimum lysine concentrations of 78%, 50%, and 78% (dry matter basis), respectively. They are designed for inclusion in premixtures, complementary feed, compound feed, or drinking water.
When used as a **sensory additive or flavouring compound**, the current maximum permitted level is **25 mg L-lysine per kg of compound feed**. However, the EURL has noted that the standard **EU method for determining lysine in compound feed is unsuitable** at such low concentrations. Instead, it recommends the **ring-trial validated EU method based on IEC-VIS** for premixtures and compound feed with higher lysine content. For **free lysine in additives and premixtures containing over 10% lysine**, the EURL suggests the **EN ISO 17180 method**. The applicant has also proposed a **modified EU method** for these cases. Identification of L-lysine monohydrochloride, meanwhile, should follow the **Food Chemical Codex (FCC) monograph**, according to the EURL's guidance. Scientific risk assessments are provided by the **European Food Safety Authority (EFSA)**, but the **European Commission's DG SANTE and national reference laboratories** remain responsible for **official control and method validation** under **Regulation (EC) No 152/2009**.
The authorisation process will determine whether the proposed L-lysine additives meet regulatory standards for safety and efficacy. If approved, they will be permitted for use as nutritional and flavouring additives in animal feed. The EURL's recommended methods will then guide laboratories in verifying compliance with the specified lysine concentrations and inclusion limits.
