Optical Character Recognition (OCR) converts images into characters for text searching. Because OCR is time and resource intensive, performing OCR during scanning significantly reduces your efficiency. Symphony OCR performs the OCR task in a background process, allowing you to turn OCR off during scanning. This procedure covers how to disable OCR when scanning using Adobe Acrobat.
Note that this setting is made on a per-user basis, so you'll have to do it for each user on a given workstation (you can thank Adobe for that - if anyone does figure out a way to get this turned off using a registry setting or anything like that, please let us know).