L-Glutamic acid - 2b620i, Monosodium glutamate - 2b621ii

In the current application an authorisation is sought under Article 4(1) for L-glutamic acid and monosodium L-glutamate monohydrate produced using the strain Corynebacterium glutamicum NITE BP-01681, under the categories/functional groups 2(b) 'sensory additives' / 'flavouring compounds' and 3c 'nutritional additives' / 'amino acids, their salts and analogues', according to Annex I of Regulation (EC) No 1831/2003. The authorisation is sought for all animal species. 

According to the Applicant, the feed additives (L-glutamic acid and monosodium L-glutamate monohydrate) are white crystalline powders with a minimum purity (mass fraction) of 98 % (based on anhydrous weight). The feed additives are intended to be added directly into feedingstuffs or through premixtures and water for drinking. The Applicant proposed no minimum or maximum content of L-glutamic acid and monosodium L-glutamate monohydrate in feedingstuffs when used as nutritional additives, while inclusion levels of up to 10 g of L-glutamic acid and monosodium L-glutamate monohydrate/ kg feedingstuffs were suggested by the Applicant when used as sensory additives. 

For the quantification of glutamic acid and monosodium glutamate in the feed additives and premixtures the Applicant submitted the ring-trial validated method EN ISO 17180:2013 dedicated for the determination of lysine, methionine and threonine in commercial amino acid products and premixtures containing more than 10 % of amino acid. The method does not distinguish between the amino acids and their salts, or between different salts of the same amino acids, and it cannot differentiate between enantiomers. The Applicant presented the results from validation and verification studies demonstrating the extension of scope of the above mentioned method for the determination of glutamic acid and monosodium glutamate in the feed additives and premixtures. The following performance characteristics were reported for the determination of glutamic acid and monosodium glutamate in the feed additives and premixtures: a relative standard deviation for repeatability (RSDr) ranging from 0.3 to 5.3 %, a relative standard deviation for intermediate precision (RSDip) ranging from 0.3 to 5.6 % and a recovery rate (RRec) ranging from 97 to 103 %. 

Based on the performance characteristics available, the EURL recommends for official control the ring-trial validated method EN ISO 17180:2013 based on IEC-VIS/FLD for the quantification of glutamic acid and monosodium glutamate in the feed additives and premixtures. 

For the quantification of glutamic acid and monosodium glutamate content in feedingstuffs the Applicant submitted the ring-trial validated European Union (EU) method (Commission Regulation (EC) No 152/2009) based on IEC with photometric detection (VIS). This method, designed for the analysis of amino acids in premixtures and feedingstuffs, does not distinguish between the amino acids and their salts or between different salts of the same amino acids and it cannot differentiate between enantiomers. 

The EU method was further ring-trial validated resulting in the EN ISO 13903:2005 method. The following performance characteristics were reported for the quantification of glutamic acid in feed at mass fractions ranging from 15.1 to 79.7 g/kg: RSDr ranging from 0.9 to 2.7 % and a relative standard deviation for reproducibility (RSDR) ranging from 4.7 to 9.1 %. Furthermore, a limit of quantification (LOQ) ranging from 30 to 350 mg/kg has been reported for the analysis of various amino acids, while a specific LOQ for glutamic acid (or monosodium glutamate) has not been indicated. 

In addition, based on NRL's experience and following the previous reports for various amino acids, the EURL recently recommended in the frame of another evaluation report for monosodium L-glutamate (FAD-2018-0090) the above mentioned EU method for the quantification of monosodium glutamate in the feed additive. 

Based on the overall available data, the EURL recommends for official control the ring-trial validated EU method, based on IEC-VIS to quantify glutamic acid and monosodium glutamate in the feed additives, premixtures and feedingstuffs (only when they are intended to be used as nutritional feed additives).

Since it is not known what will be the maximum recommended content authorised for glutamic acid and monosodium glutamate in feedingstuffs when they are used as sensory additives / flavouring compounds in the frame of the current dossier, the EURL is unable to recommend the EU method for the official control of glutamic acid and monosodium glutamate in feedingstuffs when they are intended to be used as sensory additives. However, the EU method is at least fit-for-purpose for the quantification of glutamic acid and monosodium glutamate in feed in the validated concentration range. 

For the quantification of glutamic acid in water the Applicant submitted the ring-trial validated EN ISO 13903:2005 method, which is equivalent to above mentioned EU method. This method was successfully applied in the frame of the stability studies of glutamic acid in water. Hence, the EURL recommends for official control the above mentioned EU method based on IEC-VIS to quantify glutamic acid and monosodium glutamate in water. 

For the identification of the feed additives the EURL recommends the “L-Glutamic acid” and "Monosodium L-glutamate" monographs of the Food Chemical Codex (FCC).

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, as last amended by Regulation (EU) 2015/1761) is not considered necessary.

Recommended Method

as of:

- Commission Implementing Regulation (EU) 2022/1420

For the identification of L-glutamic acid in the feed additive:

Food Chemical Codex monographs: ‘L-Glutamic acid’

For the quantification of glutamic acid in the feed additive:

Ion-exchange chromatography coupled with post-column derivatisation and visible or fluorescence detection (IEC-VIS/FLD) or

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

For the quantification of glutamic acid in premixtures:

Ion-exchange chromatography coupled with post-column derivatisation and visible or fluorescence detection (IEC-VIS/FLD) or

Ion-exchange chromatography coupled with post-column derivatisation and photometric detection (IEC-VIS), Commission Regulation (EC) No 152/2009 (Annex III, F)

For the quantification of glutamic acid in feedingstuffs:

Ion exchange chromatography coupled to post-column derivatisation and photometric detection (IEC-VIS), Commission Regulation (EC) No 152/2009 (Annex III, F)

For the identification of monosodium L-glutamate monohydrate in the feed additive:

Food Chemical Codex monographs: ‘Monosodium L-glutamate’

For the quantification of monosodium glutamate in the feed additive:

Ion-exchange chromatography coupled with post-column derivatisation and visible or fluorescence detection (IEC-VIS/FLD) or

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

For the quantification of monosodium glutamate in premixtures:

Ion-exchange chromatography coupled with post-column derivatisation and visible or fluorescence detection (IEC-VIS/FLD) or

Ion-exchange chromatography coupled with post-column derivatisation and photometric detection (IEC-VIS), Commission Regulation (EC) No 152/2009 (Annex III, F)

For the quantification of monosodium glutamate in feedingstuffs:

Ion exchange chromatography coupled to post-column derivatisation and photometric detection (IEC-VIS), Commission Regulation (EC) No 152/2009 (Annex III, F)