We have developed a recipe search engine www.edamam.com and serve the content of over 500+ food bloggers and major recipe websites. Our legal obligations do not allow us to show the actual recipe preparation info (e.g. the most valuable from the content), we can only show a few images, the ingredients and nutrition information. Most of the unique content goes to the source/blog.
By submitting XML sitemaps on GWT we now have around 500K pages indexed, however only a few hundred appear in Google's main index and we are looking for a solution to include all of them in the index.
Also good to know is that it appears that all our top competitors are in the exactly same situation, so it is a challenging question.
Any ideas will be highly appreciated!
Thanks,
Lily