When food is taken into the mouth, tiny particles break off the surface of the food and dissolve into the saliva. The saliva washes down openings in small bumps on the tongue (papillae), reaching the microscopic taste buds within.
Inside the taste buds, chemo-receptor cells detect each of the 5 basic tastes: sweet, sour, salty, bitter, and savory. This information is relayed through the cranial nerves to gustation areas in the brain, where they are processed.
Taste (gustation) detects and categorizes water soluble molecules (sometimes called tastants) that dissolve in our saliva and interact chemically with our taste buds.