Formal:
* J'adore le chewing-gum à la fraise. (This literally means "I adore strawberry chewing gum," but is the most common way to say "I love bubblegum" in French.)
Informal:
* J'aime beaucoup le chewing-gum. (This means "I like chewing gum a lot.")
* J'aime trop le chewing-gum. (This means "I love chewing gum," using a more colloquial expression.)
* J'adore le chewing-gum ! (This means "I love chewing gum!" with an exclamation mark to express stronger feelings.)
You can also use the specific color of the bubblegum if you like:
* J'adore le chewing-gum rose. (I love pink chewing gum)
* J'aime beaucoup le chewing-gum bleu. (I like blue chewing gum a lot)
Remember that "bubblegum" doesn't have a direct translation in French. "Chewing-gum" is the most common term.