I've noticed in settings for MS Word for MacOSX there is this option:

Output and Sharing > Save > Save AutoRecover info every: #x minutes

The default appears to be 10 minutes if this option is enabled. This figure can be reduced to one minute. Is there such an option for the Windows MS Word?

But as sleepybear91 pointed out, I don't know how reliable this is. Then the question is where is the document saved in auto-save mode and does it also apply to previously unsaved documents. I haven't tested this out.

I'd recommend saving and naming the document soon or immediately after you create it. In that way it should be auto-saving (in theory) if that option is enabled. If the document is purely being used as a scratch (to make quick notes within) work document to delete later then you can choose to delete the document after your work is finished within the document and the need for the document has passed. Or create a Word document saved with a name such as Scratch where the contents can be deleted or over-written after you have finished with it.