I misinterpreted the results
I was still able to retrieve email data from an FTK keyword search but not any data which was saved on the hard drive
There is something about the download method used by Microsoft that allows me to see the last 2-5 emails sent on the Windows Outlook app, with a matching keyword to the one I searched e.g.
On the 20th of December 2016 I created 3 VMs and emailed from within each one
" Today is Monday, no longer the holidays, Today is Tuesday, no longer the holidays, Today is Wednesday, no longer the holidays"
After a DBAN wipe I created a VM and emailed
" Today is Saturday, no longer the holidays"
After another DBAN wipe I created a VM and emailed
"Today is Sunday, no longer the holidays"
When the last VM created after the DBAN wipe was put into FTK Toolkit with the keyword search 'no longer the holidays' I was able to see the email sent post wipe (Saturday/Sunday) but not pre-wipe
This is just my observation )