Nonanoic acid as a feed flavouring: recommended maximum for poultry for fattening and reared, piglets and pigs for fattening raised from 5 to 100 mg/kg, for laying hens, sows and others it stays at 5 mg/kg; EFSA — in tolerance trials recovery of the acid from feed only 58–72 %, conclusions based on measured content, batch purity 98.2 %
Commission Implementing Regulation (EU) 2025/183, published on 3 February 2025, amends the authorisation of nonanoic acid (Regulation 2017/53, sensory additive, flavouring compound for all species). The recommended maximum content in complete feed with 12 % moisture is now 100 mg/kg for all poultry for fattening, poultry reared for laying or breeding, piglets (suckling and weaned) and pigs for fattening of all Suidae, and 5 mg/kg for other species and categories. It is based on the EFSA opinion of 1 February 2024.
- Tolerance trials (EFSA): the applicant submitted four — chickens for fattening, laying hens, turkeys for fattening and weaned piglets, with doses of 100, 300 and 1,000 mg/kg (1×, 3×, 10×). Recovery of nonanoic acid from the experimental feeds was low (turkeys 62–67 %, piglets 58–72 %), so the conclusions were based on the analysed, not the intended content; the EU reference laboratory considered the in-house validated method for nonanoic acid in feed for these species appropriate.
- Results: no adverse effects in chickens for fattening at 240 mg/kg (margin of safety 2.4 for 100 mg/kg, extended to chickens reared for laying), in turkeys at 630 mg/kg (only a lower, non-relevant serum ALT activity) and in piglets at 724 mg/kg (margin 7.2, extended to suckling piglets and pigs for fattening). The laying hen trial was not considered — blood sampling problems produced few samples and high variability, and the highest dose did not reach 10 times the proposed level.
- For laying hens, turkeys for breeding, minor poultry species for laying and breeding and reproductive pigs EFSA could not confirm the safety of 100 mg/kg; from the NOAEL of a toxicological study it calculated safe concentrations of 10 mg/kg (laying and breeding poultry) and 20 mg/kg (reproductive pigs). The act keeps the recommended 5 mg/kg for those categories. The 2013 conclusions on consumer and environmental safety do not change.
- Specification in the authorisation: purity above 98 %; three batches — average 98.2 % (98.1–98.2 %), in which arsenic, lead, mercury and cadmium were also determined. Efficacy need not be demonstrated, as nonanoic acid is a recognised food flavouring. For lack of data EFSA could not assess skin and eye irritancy or dermal and respiratory sensitisation.