17 Neurogastronomy

Taste and flavor are not synonymous. When humans eat, molecules bind with sensory receptors in the mouth and retro-nasal passageway, activating spatial patterns in the olfactory bulb as we breathe out. These signals combine with information from the other senses to form a neural cascade that passes through the emotion, learning, and memory-processing structures in the brain before becoming conscious perception. This is flavor. Subjective, neurologically involved, internally produced: as automatic as breathing yet as intimate as dreaming.

Flavor does not reside in food. The particular mix of molecules – the molecular gestalt of “pomegranate” or “McNuggets” – engages all five sense in crossmodal interactions that produce “odor images” with specific implications for our perception of food. The images are heavily dependent on our behavior: whether we’re sad, hungry, amused or suspicious of the food or ingestion ritual we are engaged in. They are also contingent on the environment: noise, light, temperature all change the way food tastes and we process it.

Human beings have 1,000 olfactory genes, comprising 1-2 percent of the genome. What’s more, the food molecules we sense evolved to carry out specific functions like communication between plants, defence against pests or responses to environmental shifts. Consider the way the flavor of tomatoes seems to improve after being exposed to excessive UV light (as in the varieties sold as “sun-ripened” or “sun-blanched”). All molecules exist within a broad matrix of chemical, biochemical, ecological, and evolutionary purposes. In a quite literal sense, we can taste the operations of the biosphere. Because these molecules combine with images, language and memory, we can taste ideology as well. The study of flavor perception as it relates to sense and memory is a burgeoning science known as “neurogastronomy.”