"Gum manufacturers try to keep their recipes top secret, but the Wrigley Company acknowledges that most gum is made from four basic components: sweeteners, softeners, flavorings, and gum base.
Those first three categories include ingredients such as sugar, corn syrup, aspartame, glycerin, vegetable oil, and natural and artificial flavorings such as spearmint or cotton candy. These ingredients are all soluble, meaning your saliva will dissolve them as you chew.
This is where the fourth component--gum base--comes in. The gum base stands up to your saliva and maintains its integrity as you grind it between your teeth or blow it into a bubble. Historically, gum base was tapped from natural sources like sorva, jelutong, and chicle, the sap from sapodilla trees."
To learn more, read the book:
"Why Do Men Leave The Seat Up?"