Tea oil is a sweet seasoning and cooking oil made by pressing the seeds of Camellia sinensis or Camellia oleifera . Tea oil is a sweet seasoning and cooking oil made by pressing the seeds of the Oil-seed Camellia ( C. oleifera ) , the Japanese Camellia ( C. japonica ) , and to a lesser extent other species such as Crapnell 's Camellia ( C. crapnelliana ) , C. reticulata , C. sasanqua and C. sinensis . Relatively little-known outside East Asia , it is the most important cooking oil for hundreds of millions of people , particularly in southern China .