When the new .msg export functionality was added in FileLocator Pro 7.5 another option Add separate message body text attachment was added to preserve the ability to export emails as text files:

With that option checked a separate text file is added to the results, which represents the email body as a text file. For example, to extract the emails of a folder in a PST file as text files you'd perform a search like this:
File name: *.txt
Containing text:
Look In: C:\MyEmail.pst\Inbox
Each result will represent the body of the email and when copied or exported to a folder will be extracted as a text file.