How to change color of background of scans

[Russell Abbott 0]

Using trial version of Nitro Pro 12 on PC with Windows 7 with a Kodak scanner.

I am trying to scan using the "create a pdf" drop down menu in Nitro. Not sure if it is taking my preferences. But the main problem is the scans have a very gray background instead of white. 

I think it is trying to do a color scan even though I'm not wanting to. Is there a manual fix for the scan background?

Thanks!