When saving a JPEG the default is a 3 when I would like to save as a 12 as global

How do I set a global prefermance for saving a JPED to maximum.  A little more detail when a JPEG is edited. File save as, the dialog box comes up with various options but it is always a 3 not a 12.  Where is the setting to change to a 12 rather than a 3?