CDG 25

The Chemically Defined Flavourings - Group 25 (CDG25, phenol derivatives containing ring-alkyl, ring-alkoxy, and side-chains with an oxygenated functional group), in this application comprises 16 substances, for which authorisation as feed additives is sought under the category "sensory additives", functional group 2(b) "flavouring compounds", according to the classification system of Annex I of Regulation (EC) No 1831/2003.

In the current application submitted according to Article 4(1) and Article 10 (2) of Regulation (EC) No 1831/2003, the authorisation for all species is requested. The flavouring compounds of interest have a purity ranging from 96 % to 99 %. 

Mixtures of flavouring compounds are intended to be incorporated only into feedingstuffs or drinking water. The Applicant suggested no minimum or maximum levels for the different flavouring compounds in feedingstuffs. 

For the identification of volatile chemically defined flavouring compounds CDG25 in the feed additive, the Applicant submitted a qualitative multi-analyte gas-chromatography mass-spectrometry (GC-MS) method, using Retention Time Locking (RTL), which allows a close match of retention times on GC-MS. By making an adjustment to the inlet pressure, the retention times can be closely matched to those of a reference chromatogram. It is then possible to screen samples for the presence of target compounds using a mass spectral database of RTL spectra. The Applicant maintained two FLAVOR2 databases/libraries (for retention times and for MS spectra) containing data for more than 409 flavouring compounds. These libraries were provided to the CRL. The Applicant provided the typical chromatogram for the CDG25 of interest. 

In order to demonstrate the transferability of the proposed analytical method (relevant for the method verification), the Applicant prepared a model mixture of flavouring compounds on a solid carrier to be identified by two independent expert laboratories. This mixture contained twenty chemically defined flavourings belonging to twenty different chemical groups to represent the whole spectrum of compounds in use as feed flavourings with respect to their volatility and polarity. Both laboratories properly identified all the flavouring compounds in all the formulations. Since the substances of CDG 25 are within the volatility and polarity range of the model mixture tested, the Applicant concluded that the proposed analytical method is suitable to determine qualitatively the presence of the substances from CDG 25 in the mixture of flavouring compounds.

Based on the satisfactory experimental evidence provided, the CRL recommends for official control for the qualitative identification in the feed additive of the individual (or mixture of) flavouring compounds of interest (listed in Table 1) the GC-MS-RTL (Agilent specific) method submitted by the Applicant. 

As no experimental data were provided by the Applicant for the identification of the active substance(s) in feedingstuffs and water, no methods could be evaluated. Therefore the CRL is unable to recommend a method for the official control to identify the active substance(s) of interest (cf. Table 1) in feedingstuffs or water. 

No further testing or validation is required.

Recommended Method

as of:

• Commission Implementing Regulation (EU) 2022/1250
• Commission Implementing Regulation (EU) 2024/1989

For the identification of 3-methylphenol, 3,4-dimethylphenol, 2-Methoxyphenol, Thymol, 2-Methoxy-4-methylphenol, 4-Ethylguaiacol, 2-Methoxy-4-vinylphenol, 4-Ethylphenol, 2-Methylphenol, 4-Methylphenol, Carvacrol, 2,6-Dimethoxyphenol, Phenol, 2,6-Dimethylphenol, 2-Isopropylphenol, Benzene-1,3-diol in the feed additives and in feed flavouring premixtures:

• Gas chromatography mass spectrometry with retention time locking GC-MS-RTL