Food donated to a zoo to feed the animals was cooked and served in the cafe.
Woburn Safari Park in Bedfordshire received a batch of fresh vegetables after an accidental double delivery at a nearby supermarket.
Those that were not suitable for the animals - a quantity of potatoes and onions - were used in the kitchen, it was revealed.
The incident in September 2009 came to light after a complaint was made to the local council.
Council officers investigated and discussed with the operators measures to tighten up their procedures, with the zoo being banned from using donated food in this way in future.
But the park said the produce was always meant for human consumption and was served in the cafe so it would not have to be thrown away.
A spokesman said: "In September 2009, Woburn Safari Park received a one-off delivery of surplus fresh vegetables from a company due to a stock overbooking.
"The produce, always intended for human consumption, was within its sell-by dates so common sense was applied, allowing the kitchen to use those vegetables that did not suit the dietary requirements of the animals (specifically potatoes and onions) to avoid waste.
"At no point was there a risk to food safety through cross-contamination.
"The vegetables were delivered directly to the kitchen as a normal delivery would be.
"Woburn is regularly inspected by the Central Bedfordshire Council and always has good levels of food hygiene."
Central Bedfordshire Council said the park had implemented improvements suggested to it following the incident.
Councillor David McVicar, portfolio holder for safer communities and healthier lifestyles, said: "We understand that this was an isolated incident and we have received no further complaints of a similar nature, but our officers did discuss with the operators measures to tighten up their procedures in this area.
"Woburn is routinely inspected by the council and has recorded good levels of food hygiene with high confidence in management and good safe systems in place.
"As the incident happened some time ago and as Woburn Safari Park has implemented the improvements that were recommended to them, we now consider the matter closed.
"We will continue to monitor the cafe with unannounced inspections as we do with all food outlets."