I've got a new post up at Science in My Fiction that takes a look at science fictional food pills, tablets and other sorts of "people chow".
For more discussion of the history of the way Americans have imagined "future foods", I suggest checking out Warren Belasco's Meals to Come: A History of the Future of Food (sample chapter, Amazon.com, Barnes & Noble, Google Books). I've found it to be really interesting.
Read "Soylent Green for Dinner?" at Science in My Fiction
( Photo by epSos.de on Flickr )