I thought chewing gum already helped freshen ones breath.  At least it worked for me.  Apparently, Wrigely thought the current gum lineup didn't go far enough in combating halitosis.  NutraIngredients.com has an article about the patent.

Wrigley, who own the brands Juicy Fruit, Extra and Doublemint, claim the gum is an improvement on existing brands as contains enough flavour to mask any unpalatable taste.

The patent, 7,087,255, entitled "Chewing gums that provide breath freshening characteristics" puts it this way in the abstract . . .

A coated chewing gum is provided that includes a metal salt. The salt can be located in the gum center, coating, or both. A metal salt is provided in a therapeutically effective amount to reduce or eliminate oral malodors associated with bad breath. A variety of metal salts are possible. The coating may also include a surfactant and an edible oil.