Has there ever been an attempt to create nutritionally tailored food for adult human consumption?
Yes.  Rob Rhinehart has developed what he refers to as &quot;a food substitute intended to supply all of a human body's daily nutritional needs, made from powdered starch, rice protein, olive oil, and raw chemical powders&quot; which he calls Soylent.
It was developed and tested largely in 2013, crowdfunded late 2013, and is expected to start shipping in 2014. Tests of at least 30 days with no other food intake have been performed, though this is being marketed as a food and not a medical aid of any sort, so does not require FDA testing.
Even if this didn't exist, there are numerous &quot;complete&quot; human diet foods meant for medical use.  These are mentioned in an article about soylent:

Jay Mirtallo is a professor of pharmacy at Ohio State and the immediate past president of American Society for Parental Enteral Nutrition, which focuses on the science and practice of providing food to patients through both intravenous injections and feeding tubes. His main concern with Rhinehart's plan is that he's making the concoction himself, rather than buying it from reputable suppliers.
&quot;He basically made medical food,&quot; Mirtallo says. &quot;If he wanted to switch to a liquid diet, those are already available.&quot;
Indeed they are. Companies like Abbott Nutrition and NestléHealthScience sell dozens of medical food products, intended to be used by patients under medical supervision and administered intravenously, orally, or through an incision in the stomach.
&quot;They’re very complex products, in terms of making sure you get them in a form that’s palatable but that stays in a form that’s bioavailable to the body,&quot; Mirtallo says. &quot;Some of the products are very difficult to get into a liquid form and may lose their potency when they do that, or could interact with other substances that keep them from being absorbed completely.&quot;

Rob appears to be attempting to make a consumer version, and so far reports are positive.
But even if you don't trust Rob's mixture, there are countless medically complete nutritional foods that are FDA approved, though not generally available at the supermarket.