The plant, which is based in the north of the Netherlands, will process 5,000 metric tonnes of whey ingredients and 25,000 metric tonnes of lactose per annum.
It will operate 24 hours a day, every day of the year, and employ 50 people. Production began on 1 January.
A-ware Food Group, who Fonterra jointly developed the site, launched a cheese plant on the site which has also been commissioned on schedule. It was built on a 25-hectare site.
Fonterra chief executive Theo Spierings said the new plant will further improve its global and European customer base.
“The new plant further strengthens our ability to deliver high-quality, advanced dairy nutrition that meets the needs of our priority markets and global customers," he said.
"Our partnership with A-Ware Food Group fits well with our strategic priorities aimed at increasing the volume and value of our ingredients and branded products."