Around two dozen Rail Gourmet staff employed on the LNER line are on their third day of strike action amid allegations of bullying by management.
The RMT union said the dispute was centred on claims of bullying and harassment of workers, abuse of the disciplinary procedures as well as non-payment of additional duties.
Rail Gourmet staff provide supplies and logistics for getting food on board the service.
RMT general secretary Mick Cash said: “Our members at Edinburgh Waverley are standing rock solid this morning in a strike for workplace dignity and justice.
“We have received fantastic support from members of the travelling public who are disgusted, as we are, at the way that Rail Gourmet are treating this particular group of rail workers.”
He said members are “resilient” and determined to win their fight following a breakdown in talks.
A Rail Gourmet spokesman said previously: “Although a small number of employees in Edinburgh are taking strike action, we do not expect this to disrupt our operations.
“If any of our customers are inconvenienced by these events, we would like to apologise and reassure them we are in active discussions with the RMT to try to resolve this as quickly as possible.”
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