The original raw materials (coffee, tea leaves, etc.) contain caffeine, and when the caffeine is removed before making it into a beverage, it is called decaf. There are three types of extraction methods: organic solvent extrac tion, water extraction, and supercritical carbon dioxide extraction, but organic solvent extraction is harmful to the body. Organic solvent extraction is easy and inexpensive, so it is still widely used overseas, so be careful. It seems that research is progressing to create genetically modified coffee plants in the future, but it's also a bad idea to make genetically modified foods even though you don't want to be inoculated with caffeine because you're conscious of your health.