Granny Smith Apples

The Granny Smith green apple is a tip-bearing apple cultivar, which originated in Australia in 1868.^[1] It is named after Maria Ann Smith, who propagated the cultivar from a chance seedling. The tree is thought to be a hybrid of Malus sylvestris, the European Wild Apple, with the domestic apple M. domestica as the polleniser. The fruit has hard, light green skin and a crisp, juicy flesh.
Granny Smiths go from being yellow to turning completely green.^[2] The acidity mellows significantly, and it then takes on a balanced flavour.