Can Quicktime Player Save Recordings as an MP3 by Default?

Quicktime Player allows a very nice workflow for recording audio for Google Slides – right up to the point where you try to insert the M4A audio file that comes out of Quicktime Player. Then Google refuses to play nicely and the workflow becomes ugly… Perhaps it's the smoke out here on the west coast, but my Google foo is failing to find any defaults settings that would change the format of the saved file (without having to go back and convert it). Is there any way to have the default format for audio recordings be MP3 instead of M4A?