Copper chelate of hydroxy analogue of methionine

Mintrex Cu is a product for which authorisation is sought under the category "nutritional additives", functional group 3b "compounds of trace elements", according to the classification system of Annex I, of Regulation (EC) No 1831/2003. According to the applicant, Mintrex Cu contains 15% of Copper as chelate of hydroxyl analogue of methionine, 2-hydroxy-4-methylthiobutanoic acid (HMTBa) as active substance. Mintrex Cu is also a source of methionine activity as HMTBa.

In the current application authorisation is sought for use of Mintrex Cu for all animal species. Mintrex Cu  is intended to be added to complete feed to supplement Cu within legal limits for each species which are: piglets up to 12 weeks 170 mg/kg, other pigs 25 mg/kg, milk replacers 15 mg/kg, other complete feed for bovine before the start of rumination 15 mg/kg, other bovine 35 mg/kg, ovine 15 mg/kg, fish 25 mg/kg, crustaceans 50 mg/kg and other species 25 mg/kg.

For the determination of Cu in the feed additive, premixtures and feedingstuffs for official control the CEN standard method EN 15510:2007, as proposed by the applicant, is recommended by the CRL.

The proposed method for the determination of HMTBa in the feed additive is considered suitable for the intended purpose.

The suitability of the proposed method for the determination of HMTBa in feedingstuffs cannot be evaluated by the CRL.

Recommended Method

as of:

- Commission Implementing Regulation (EU) 2023/1334:

For the quantification of the hydroxy analogue of methionine content in the feed additive: 

• Titrimetry, potentiometric titration after oxidation reduction reaction

For the quantification of total copper in the feed additive:

• Inductively coupled plasma atomic emission spectrometry, ICP-AES (EN 15510 or EN 15621) or 
• Atomic absorption spectrometry, AAS (ISO 6869)

For the quantification of total copper in premixtures:

• Inductively coupled plasma atomic emission spectrometry, ICP-AES (EN 15510 or EN 15621) or
• Atomic absorption spectrometry, AAS (ISO 6869) or
• Inductively coupled plasma mass spectrometry, ICP-MS (EN 17053).

For the quantification of total copper in compound feed:

• Inductively coupled plasma atomic emission spectrometry, ICP-AES (EN 15510 or EN 15621) or
• Atomic absorption spectrometry, AAS (Commission Regulation (EC) No 152/2009 (Annex IV-C) or ISO 6869) or
• Inductively coupled plasma mass spectrometry, ICP-MS (EN 17053).