About 30 jobs at Fonterra's Canpac plant are being axed as low milk prices push the dairy giant to cut costs.
Fonterra has met with staff at its Hamilton canning plant, saying it would be outsourcing its press and print roles because of low demand.
It's the second job cull of Canpac since 2014 when 104 positions went as the company cut back its operation to five days instead of seven days a week.
E tū has 21 workers whose roles are affected at the Hamilton plant.
The union's national Fonterra advocate Fiona McQueen said there was a great feeling of sadness among the workers.
"These workers have worked together for a long time, and they've worked really hard."
She said while they had been given options to be redeployed elsewhere, metal decorators in particular would be hard-pressed to find similar skilled jobs.
In a statement, Fonterra's director of New Zealand Manufacturing, Mark Leslie, said they had been working closely with staff who could either fit into another role within Fonterra or opt to take redundancy.
He said the operations of press and print would be taken elsewhere.
"With reduced demand in these parts of the business and taking into account the cost efficiencies of outsourcing - particularluy at a time of low milk price - it is important we consider all alternatives that will drive cash back to our farmers."
The press roles would be disestablished at of the start of July and the print roles at the end of July.