I believe that LSG does emirates, and the food ex-AKL in both F and J is of a considerably higher standard than NZ
Although I understand that some components are shipped in from their mega-kitchen in Dubai as freight and go out the following day as meal components, but the bulk of the main meals are ex-AKL.
So NZ is extra bad. You would assume that LSG provides the quality the airline pays for.

Is it possible that NZ has a crew/preparation and service problem? Or is it largely down to the quality of ingredients?