The union representing food workers at the Southern District Health Board says they will find out next week if their work will be outsourced to another company - with the possibilty of one in five workers losing their jobs.
About 300 people protested today at the Octagon in Dunedin.
The Service and Food Workers Union said the Government planned to outsource food services at DHBs around the country.
Three Auckland boards have already signed a deal with the multinational firm Compass.
The union said it had submitted a counter-proposal that would achieve savings without the loss of jobs and would put its case to the Southern DHB board next Thursday.
Its Southland organiser, Anna Huffstutler, said it had been estimated 20 percent of jobs would be lost but there had been no detail on what those positions would be. She said the proposal would also affect local food producers.
The board's acting chief executive, Lexie O'Shea, said it was currently consulting with staff and a food services paper will be considered at the next board meeting.