The whole production area cost under $1 million.
Hansells Engineer Robin Shaw said everyone involved in the project had worked well together.
"Quite a few contractors and locals were involved, from painters, to floor layers, and all sorts of tradies have been in," he said.
"And if this all takes off the way we hope it will, it should really be a bright future for Hansells."
Mr Stewart said Masterton's Hansells have already shipped a 40ft container of yoghurt mix powder to Italy with prospects for other countries.
"We got underway with our limited facilities and have already sent half a million dollars worth of products to China and expect to be regularly shipping 40ft containers of dairy products to China in the New Year using these facilities."
Masterton Mayor Lyn Patterson was at the opening and said she was pleased Hansells was expanding.
"It just shows that our local businesses are innovative, and are looking at different markets and different ways to get ahead. And that's so important for our community because so many people are employed here."