Teas

Green tea leaves are high in amino acids including glutamate and theanine, which displays low levels of umami and sweetness. Most of the black teas and oolong teas distributed widely throughout the world are what are known as fermented teas. In order to color the leaves and the tea itself brown and produce a unique depth of flavor and aroma, these teas are made by triggering the enzyme oxidase in the tea leaves under humid conditions. Because this fermentation process alters the amino acids such as glutamate in the leaves, fermented teas do not contain umami. Green tea on the other hand is a non-fermented tea, made by steaming the leaves without allowing enzymatic oxidation. This means that the glutamate and theanine in the tea leaves are preserved along with the umami.