Crystal Tadlock says a Delta flight attendant gave her an apple toward the end of her flight from Paris.
She took the piece of fruit and put it in her carry-on bag. When she went through customs, an agent pulled out the apple in a plastic pouch from Delta.
"He had asked me if my trip to France was expensive and I said, well yeah, I didn't understand why he was asking that question, and he said 'it's about to get a whole lot more expensive after I charge you $500," said Tadlock.
Tadlock says Delta should not have given out apples or at least warned passengers not to take them off the plane.
In a statement, Delta would only say, 'they encourage customers to follow U.S. Customs and Border Protection protocols.'
The fine was issued because Tadlock did not declare she was bringing the apple into the U.S. Customs declaration forms ask passengers if they are bringing any fruits or vegetables into the country.
The Associated Press contributed to this report.