I recently saw an image that perfectly encapsulates many of my current interests, including odor and flavor mapping, the senses in scientific analysis, medieval ideas about health and disease, body fluids, and metabolic profiling. The Urine Wheel was used for diagnosing diseases based on the color, smell, and taste of the patient's urine in the early 16th century:

Many diseases affect metabolism and many changes in metabolism can be detected in the urine. For example, diabetics will excrete sugar in their urine--sometimes enough sugar that it can be fermented into whisky. There are many other diseases that change the smell of a person's urine, including the very descriptively named Maple Syrup Urine Disease or Sweaty Feet Syndrome, now much more likely to be diagnosed by electronic sensor arrays than actually tasting the urine. I'm fascinated by all the ways that people categorize and arrange information about flavors and odors, as wheels or otherwise, and the ways that those arrangements affect our perception, consumption, and even diagnosis.