sweetener vs sweetening

sweetener and sweetening both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweetener	Yes	No	No	No
sweetening	Yes	No	No	No

As nouns, sweetener and sweetening are synonyms defined as:

sweetener and sweetening: something added to foods to make them taste sweeter

sweetener (noun)	sweetening (noun)
anything that serves as an enticement	the act of adding a sweetener to food
something added to foods to make them taste sweeter	an improvement that makes something more agreeable
	something added to foods to make them taste sweeter