Fonterra is describing its Edendale Dairy Factory in Southland as the largest in the world.
The $212 million drying machine can convert an entire day's worth of milk from one dairy farm and turn it into milk powder in less than a minute.
Prime Minister John Key joined thousands of dairy farmers and members of the public at the official opening of the facility on Friday.
The machine can convert the daily production of three Southland dairy farms every two minutes - that's 1000 Southland dairy farms, 500,000 cows and 15 million litres of milk every day.
Dairy farmers are heralding the new factory and say it shows the commitment Fonterra has for the region and will allow further expansion of dairy farming in the province.
Fonterra says it will capitalise on that with predictions dairy farming will grow by 6% a year in Southland for the forseeable future.