by-product vs fruitage

by-product

noun
  • A side effect. 

  • A secondary product; something made incidentally during the production of something else. 

fruitage

noun
  • Product or result of any action, effect, good, or ill. 

  • Fruit, collectively. 

How often have the words by-product and fruitage occurred in a corpus of books? (source: Google Ngram Viewer )