Developed by Health Benefits Ltd, the business case blew out from $3.1 million to $4.1 million.
Controversially, health boards had to pay their share, whether or not they outsourced their kitchens.
For now, the invoiced amount has been shunted into ''governance'', a part of the budget allocated for running the board.
The board discussed the matter at its meeting in Invercargill yesterday, prompted by a question from member Mary Gamble.
Only $14,000 a month is allocated for governance, meaning its April total blew out to $289,000.
Finance head Peter Beirne said management was not sure where the spending belonged.
''We may reverse it and put it somewhere else [in the accounts],'' he told members.
More generally, little was said about the board's finances at the meeting.
Chairman Joe Butterfield asked Mr Beirne if the expected end-of-year position had greatly changed.
It had not, but there were still factors that would influence the final deficit.
It has been previously reported the board could post a $27 million deficit.
Recent publicity over health cuts relates to the projected $42million deficit in 2015-16, which the board is trying to forestall by cutting funding to community providers.
Food outsourcing was also raised at the previous day's hospital advisory committee meeting by member Richard Thomson, who asked about potential legal action.
The Service and Food Workers' Union sent a lawyer's letter to the board on May 8, the day after the decision to outsource.
It signalled an intention to take, but was not a confirmation of, legal action.
The board had received no further information on the matter, Mr Thomson was told on Wednesday.
