appetite vs unenthusiasm

appetite

noun
  • Desire to eat food or consume drink. 

  • The desire for some personal gratification, either of the body or of the mind. 

  • Any strong desire; an eagerness or longing. 

unenthusiasm

noun
  • Lack of enthusiasm. 

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