Gum base

Gum base is the non-nutritive, non-digestible, water-insoluble masticatory delivery system used to carry sweeteners, flavors, and any other substances in chewing gum and bubble gum. It provides all the basic textural and masticatory properties of gum.
The actual composition of gum base is usually a trade secret. The FDA allows 46 different chemicals under the umbrella of "gum base." The chemicals are posted on their website. These chemicals are grouped into the following categories.
Gum bases for chewing gum are different from those for bubble gum. A bubble gum base is formulated with the ability to blow bubbles; it contains higher levels of elastomers or higher molecular weight polymers for this purpose. Gum bases for antacid use calcium carbonate as a filler, while gum bases for acid flavored gum use talc as a filler, since acids can react with calcium carbonate to produce carbon dioxide gas, which is undesirable.
Bubble gum usually contains 15–20% gum base, while chewing gum contains 20–25% gum base and sugar-free chewing gum contains 25–30% gum base.
Researchers at the University of Illinois at Urbana–Champaign and at Wm. Wrigley Jr. Company are studying the possibility of making gum base with biodegradable zein (corn protein).
Large chewing gum manufacturers generally produce their own gum base in-house while small chewing gum producers usually buy gum base from third-party suppliers.
Composition and manufacture.
Another way to categorize the various components of gum bases is by their utility in the base.
Old gum bases were based on either natural elastomers such as latexes, vegetable gums like chicle, spruce gum, and mastic gum, or alternatively on waxes, e.g. paraffin wax and beeswax, but today synthetic rubbers are preferred.
References.
"Formulation and Production of Chewing and Bubble Gum", edited by Doug Fritz, pp 93–118, Olivias's Publications Ltd, London, UK, 2006, [DEAD LINK]