Prisons in England and Wales could be forced to bring in food from outside caterers if a 48-hour strike by industrial workers, including kitchen staff, goes ahead later this month.
Industrial staff with the Amicus trade union have voted to take strike action for two days, starting from 31 August.
They are upset over an imposed 1% pay deal, which they argue is much less than the 2.8% agreed with prison officers.
A further three unions are also balloting on action and in all it could mean 4,000 employees downing tools at the end of the month.
Amicus officer Ciaran Naidoo said, while it was unclear how many prison catering staff might be affected, the union did represent such workers.
A similar one-day strike in May resulted in shortages and disruption in some prisons, for instance over milk.
"That may not sound like much, but the prisoners do like their tea. If we strike for two days, the prison service will have to take charge of organising the catering for prisoners," he said.
During the May strike some prisons had to call in outside caterers and, for a longer strike, this was likely to be the case again, he predicted.
by Nic Paton
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