When you read our descriptions of Japanese green teas, you will often come across the term umami. But what is it? While we all know that when we eat or drink we identify sweet, sour, bitter and salty tastes, not everyone has heard of the fifth, savoury taste, umami.
What is umami?
Although it wasn’t officially recognised until 1985, umami was first identified by Japanese scientist Dr Kikunae Ikeda in 1907. He found that umami was actually glutamate, an amino acid that is one of the building blocks of protein and occurs naturally in foods such as dairy products, meat, fish and some vegetables. When these foods are cooked, the glutamate is converted to L-glutamate, which gives the food what Dr Ikeda described as a rich, intense flavour, delicious, pleasant and savoury.
Examples of foods rich in umami are tomatoes, mushrooms, seaweed, soy sauce and Parmesan cheese. The following diagram shows which types of food contain which tastes, and much more information about umami can be found on the Umami Information Centre website.
What do we taste in green tea?
Green teas contain varying amounts of sweet, umami, astringent and bitter tastes. The sweet and umami flavours are due to the presence of theanine and glutamate, both of which are amino acids. The astringent taste in green tea comes from catechins and the bitter taste from caffeine.
Teas rich in umami
Japanese green teas have higher levels of glutamate than teas grown elsewhere because of the way they are grown and processed. According to the Umami Information Centre, premium teas from the first harvest of the year, particularly Gyokuro and Sencha, contain the highest levels of umami. Like Gyokuro, Matcha has more umami because the leaves are shaded for a period of time before harvesting. In general, the earlier the tea is harvested and the longer it is shaded, the sweeter the flavour and the more umami it will have.
Green teas from other regions can also have umami but this is rare. An example of a Chinese green tea rich in umami is our Tonglu Long Jing. In this case the tea has a high level of glutamate because it is grown at a high altitude in a region where the plants are naturally shaded by clouds and fog.