There are numerous alkaloids in kratom, including mitragynine and 7-hydroxymitragynine, which are considered its two primary alkaloids. In fact, mitragynine is the Latin name of kratom.

The white vein varieties of Kratom are harvested when the leaves are still growing. As a result, grains start to germinate before being ground, similar to malting. Unlike grain-grinding, malting produces a different balance of natural sugars. Likewise, white vein Kratom has a different alkaloid profile than other varieties, and tends to contain more 7-hydroxymitragynine. Kratom with white veins often has a creamy or light tan color.

A green vein Kratom leaf is harvested when it's still in its early stages, but before it's fully mature. These leaves have stopped budding, and have begun to perform their traditional functions of photosynthesis and respiration. Different alkaloid profiles naturally result in different qualities in the finished product: green vein strains have a balanced yet versatile alkaloid profile. The color tends to be vibrant green when processed.

It's not careful harvesting that gives yellow vein strains their color, it's a small-batch drying process. A popular process in Thailand and Vietnam, this process starts with carefully selected leaves that have mature alkaloid profiles, like green vein leaves. After that, the leaves are spread on drying racks and exposed to direct sunlight for several days. During chlorosis, the leaves' chlorophyll breaks down, causing them to yellow. It's a time-consuming process, which is why yellow vein Kratom products aren't as common. As a result, this specialized variety has an alkaloid profile that reflects its long production process. Kratom with yellow veins has a golden or coppery color.

The leaves of red vein Kratom are harvested when they're fully mature. These leaves are no longer dividing their energy between growing and contributing to the tree. They now have a mellow, rich alkaloid profile, especially Mitragynine. A red vein in red vein Kratom won't make you think of a fire hydrant: red pigment adds an earthy green tone, sometimes bordering on brown.