She was told she could take her own packed meals on the plane, as long as they met regulations and did not need heating or chilling.
Ms McGunnigle said the family paid a lot for its flights, with meals included, and she did not expect to be told to bring her own.
But Air New Zealand said it tried very hard to cater for customers with different dietary needs.
"These meals are prepared by aviation caterers who prepare meals for numerous different airlines at various ports on our global network so it's necessary for us to provide a set range of options, which we hope will cater to a wide variety of dietary requirements," a spokeswoman said.
"Air New Zealand does all it can to cater for special dietary requirements.
"In Ms McGunnigle's case, this includes requesting a gluten-free vegan meal be made available for her upcoming travel."
She confirmed the airline did sometimes suggest people bring their own meals to meet cultural or health needs where they could not be provided.
Ms McGunnigle said she was pleased Air New Zealand had now ordered special meals for her, but other airlines the family was using on its trip agreed at the time of booking to provide suitable meals.
"Yes, Air New Zealand should be congratulated for resolving my situation but this is a multi-award winning company that prides itself on its customer service.
"It surprised me that it wasn't a little more enabling for travellers."