maturate vs sweeten

maturate

verb
  • To promote the perfect suppuration of (an abscess). 

  • To undergo perfect suppuration. 

  • To bring to ripeness or maturity; to ripen. 

sweeten

verb
  • To make less painful or laborious; to relieve. 

  • To supplement (a composition) with additional instruments, especially strings. 

  • To make pure and salubrious by destroying noxious matter. 

  • To make warm and fertile. 

  • To restore to purity; to free from taint. 

  • To become sweet. 

  • To soften to the eye; to make delicate. 

  • To make sweet to the taste. 

  • To make more attractive; said of offers in negotiations. 

  • To make (more) pleasant or to the mind or feelings. 

  • To make mild or kind; to soften. 

How often have the words maturate and sweeten occurred in a corpus of books? (source: Google Ngram Viewer )