1. Type of coffee bean.
There are several kinds of the coffee plants, and each of them grows best at different parts of the world. Because of unique growing conditions that influence the characteristics of the coffee bean, caffeine level in the beans harvested from different plants will vary.
Coffee plants have an ability to produce caffeine as a pesticide. The higher altitudes, the less caffeine these plants produce. It happens due to the fact that there are fewer pesticides at lower altitudes.
Let’s compare the most popular and widespread coffee types in the world – Arabica and its counterpart Robusta. Arabica grows at nearly 1300 – 1500 meters, while Robusta grows best at a maximum altitude of 600 meters. Consequently, Arabica caffeine content is lower than the Robusta. Read more about differences between Arabica and Robusta in this article.