The role of salivary amylase

It does more than just pre-digest your food, as a WSJ article explains:

While taste sensations are fairly well understood, scientists are just beginning to unravel the mystery of food texture.

Now, researchers at the Monell Chemical Senses Center in Philadelphia have found that an enzyme in saliva called amylase, which breaks down starch into liquid, could play a key role in determining the appeal of various textures of food. A new genetic study shows that people produce strikingly different amounts of amylase, and that the more of the enzyme people have in their mouth the faster they can liquefy starchy foods.

Scientists think this finding could help explain why people experience foods as creamy or slimy, sticky or watery, and that this perception could affect our preference for foods...

The role of amylase and the rate of starch breakdown also has implications for diabetes. People who digest starch quickly could be more likely to have larger spikes in blood-sugar levels and thus a need for the body to generate more insulin. This continued demand on the body might lead these people to become insulin resistant or even diabetic...

Amylase and other enzymes in saliva could also help explain food-texture preferences that are known to vary with age...

And this interesting tidbit for those of you with small children -

...adults with a gene that makes bitter tastes more intense consume fewer vegetables containing bitter compounds, such as kale or spinach.

But that genetic preference can be changed by repeatedly exposing the individual to the taste or by masking the bitterness, even at an early age, she has found. In a preliminary study with preschoolers, Dr. Duffy's group added a sweet taste to balance out the bitterness of certain vegetables—less than half a teaspoon of sugar to a cup of broccoli or asparagus, for example, during cooking—and found that the children were more accepting of the greens. Even when the sweetness was removed, the children still liked the vegetables more than before because they had developed a positive association with them