US dairy group Dean Foods has played down allegations that its new organic Horizon fat-free milk contains an additive that has not been approved for use in organic products.

Horizon Fat-Free Milk Plus DHA Omega-3, launched earlier this week, has come under fire from organic lobby the Cornucopia Institute, which claimed that the launch represented “a willful and flagrant violation of the law governing organic foods”.

US regulations prohibit synthetic additives in organic foods unless the additive appears on the USDA’s National Organic Program’s list of allowed substances, Cornucopia claimed.

“The specific type of laboratory-produced DHA oil that Horizon adds to its milk has never been reviewed by the National Organic Standards Board or approved by the USDA,” Charlotte Vallaeys, a farm and food policy analyst with the Cornucopia Institute, said.

However, a spokesperson for Dean Foods rebuffed the accusation. “The USDA has not banned the use of plant-based DHA in organic milk, nor has it questioned the safety or efficacy of the ingredient,” the spokesperson said.

“We worked with Martek Biosciences, who produces our plant-based DHA, to follow the correct process for filing a petition with the USDA to maintain plant-based DHA omega 3 as an additive to organic milk. This petition has been accepted and is under review. However, USDA has not yet concluded the formal approval process.”

The spokesperson added: “Our Horizon Organic Plus DHA Omega-3 products are certified organic, and have been since their inception. We are proud to offer the latest product in our lineup – Fat Free Milk Plus DHA Omega 3.”