http://insights.globalspec.com/article/7782/turning-to-an-unlikely-source-for-astronaut-nutrition-human-waste
"Comparing the end result to a food spread made from a beer brewing by-product popular in Australia and parts of Europe, geosciences professor Christopher House says that “The concept would be a little bit like Marmite or Vegemite, where you're eating a smear of 'microbial goo.'""