palm sugar vs panela

palm sugar

noun
  • sugar made from the sap of various species of palm tree, family Arecaceae. 

panela

noun
  • An unrefined sugar product typical of Central and South America and Mexico, which is basically a solid piece of sucrose and fructose obtained from the boiling and evaporation of sugarcane. 

  • A white, fresh, and smooth Mexican cheese of pasteurized cow's milk similar to Indian paneer. 

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