I assume this would go into DMCA territory, since your hosting user submitted content. As long as you don't host the scraped recipes and images publicly, I imagine it would live in a legal grey area if you had a notice that you must be allowed to use the image you upload in your jurisdiction.

It'd be similar to trying to go after google because someone uploaded a copyrighted work to their google drive. I know they have to deal with it if you share the link, but they don't go out of their way to remove content you uploaded to your google drive and never shared.