Green tea is dried and rolled, but not oxidized. The leaves are rolled or twisted in a variety of ways. Pan-fired greens undergo three treatments at the same time: roasting, rolling and firing. Roasting kills off the enzymes responsible for oxidization and involves heating the green tea leaves to approximately 212°F, at which point the leaves become soft and flexible, 5 ready for rolling. The leaves may be rolled into various shapes. Japanese greens are manufactured differently, by steaming rather than pan-firing. Green tea is an excellent thirst quencher and can be drunk throughout the day. Nearly all green teas come from China or Japan. Although India, Sri Lanka, Argentina and Vietnam have started producing green teas, China still remains the leader in manufacturing green teas.