feed = $.getBean("feedManager").read('F78748AB-BADD-5E7F-86890BE17C0E11E8')
Your code returns you the feedBean for your local index. The next step is to ask the feedBean for the content. The content can be returned in two formats: a Query object or an Iterator.
Query:
feed.getQuery();
Iterator:
feed.getIterator();
If you ask for the query format you can loop over it using the 'cfloop'-tag with the 'query'-attribute.
If you ask for the iterator this documentation will help you looping over an iterator in Mura (the documentation if for a content iterator, but the concept is the same): http://docs.getmura.com/developer-guides/back-end-development/content-iterator/