Papillae

Take a look at your tongue in the mirror and compare it to this picture.
As you can see in this picture (and maybe on your own tongue) there are different types of papillae on your tongue.
The largest and most posterior are the vallate papillae.
Follate papillae are elongated.
Fungiform papillae are relatively large toward the back of the tongue and much smaller along the side and tip.

Taste Cells
Each taste bud is made up of taste cells, which have sensitive, microscopic hairs called microvilli.
A taste bud is a cluster of taste cells (or receptor cells), gustatory afferent axons and their synapses with taste cells and basal cells.
Microvilli at the apical end of the taste cells extend into tatst pore, the site where chemicals dissolved in saliva can interact directly with taste cells.
Those tiny hairs send messages to the brain, which interprets the signals and identifies the taste for you.
Identifying tastes is your brain's way of telling you about what's going into your mouth, and in some cases, keeping you safe.

Have you ever taken a drink of milk that tasted 'funny'?
When the milk hit the taste buds, they send nerve impulses to your brain: "Milk coming in - and it tastes funny!"
Once your brain unscrambled the nerve impulses, it recognized the taste as a dangerous one, and you knew not to drink the milk.

Some things can make your taste bud receptors less sensitive, like cold foods or drinks.
An ice pop made from your favorite juice won't taste as sweet as plain juice.
If you suck on an ice cube before you eat a food you don't like, you won't notice the bad taste.

"No one has a right to consume happiness without producing it."