The strike by 180 SIPTU members at the Bailey’s cream liqueur manufacturing plant in Dublin, which began last Sunday, is set to enter its second week.
They are also being supported by a further sixty clerical and thirty maintenance workers.
SIPTU Branch Secretary, Ms Anne Speed said she was disappointed that workers who had contributed so much to the success of the company now found themselves having to engage in industrial action because management have so far failed to address the claims for loss of earnings and improved pay structures.
"The company is due to open a new plant in Northern Ireland next year to cope with the increased demand for its product," she said.
"Sales of Bailey’s cream liqueur are set to increase to 10 million cases over the next five years from 6 million cases at present.
"This is a measure of how well the company is doing, yet the management employed fixed term contract workers - initially at a lower rate of pay than our members - rather than address our concerns regarding future employment prospects at the Dublin plant," she said.