Don't think you can without using VBA (but, believe me, I've been wrong before!).
It will, however, insert quotes where required i.e. if a cell has a field delimiter
(comma) in it.
ex Doe,John (in one cell) will be saved as "Doe,John"
vs. Doe John (in two cells) will be saved as Doe , John
The Text Write Program, and Excel workbook with a macro that writes any
sheet to a text file with lots of options, will do that. www.smokeylake.com/excel.