To present participles which come from intransitive verbs, or are themselves employed as adjectives, to mark the absence of the activity, disposition, or condition implied by the participle;

Unripened cheeses are also known as fresh cheese. Fresh cheese hasn't been aged. The most common example of a fresh cheese would be cottage cheese.

not fully developed or mature; not ripe; "unripe fruit"; "fried green tomatoes"; "green wood"