Deep Dive Into Gyokuro

What kind of tea does Asahina Valley produce?

The tea gardens of Asahina Valley in Shizuoka prefecture typically produce this shaded green tea called Gyokuro, which is regarded by many as the highest quality, most prized green tea from Japan; the jewel of its tea making achievements as it were. Gyokuro is prized for its powerful umami flavour and lingering sweetness.

The depth of the umami comes from the shading of the tea bushes for around 3 weeks before the leaves are picked. Large sheets of netting or panels of rice straw are erected over entire fields of tea plants, blocking out 80-90% of the sunlight. Cutting out the light source in this way encourages the tea plants to produce more green chlorophyll so that they can still photosynthesise (in other words, keep growing). The chlorophyll is what gives the leaves their characteristic rich green colour, and this process concentrates some of the amino acids like L-Theanine in the leaves. L-theanine is one of the plant compounds that tastes umami.

The Asahina Valley is not where Gyokuro was originally made though, that’s Uji in Kyoto and Yame in Fukuoka. Unfortunately, the prized reputation of Gyokuro means that there is significant pressure on farmers in Uji and Yame to produce the highest yields and high quality Gyokuro. This demand, together with a differing attitude to farming in Japanese culture, has meant that these areas have steadily become saturated with pesticides and agrochemicals. In Asahina Valley however, where there is less pressure from domestic demand, we have been able to find teas produced without agrochemicals in clean and bio-diverse environments that crucially don’t compromise on the umami-rich and sweet flavour of high quality Gyokuro.

Asahina Valley is populated with luscious green tea gardens, which extend upwards on both sides of the Asahina River; a great water source that cuts through the valley, bringing plenty of nourishment to the soil. At its closest, the area is just 15kms from the Pacific Ocean, but most of the tea is grown at least 250m above it.

How did we source this batch of tea and who made it?

Our current batch of Gyokuro was produced by husband and wife, Mr & Mrs Miyazaki, who Tom (our Head of Tea) visited last Spring in the middle of their production. The young leaves and buds were picked in early May, as part of the first flush. Officially in Japanese green tea producing areas, the beginning of this first flush harvest should be 88 nights after the first day of spring is celebrated. There is a celebration day called Hachijuhachiya, which marks this. When we’re sourcing tea, we don’t tend to stick assiduously to these traditional calendars – the combination of our priority of quality of taste and recent changing weather patterns mean that they don’t always align. However we do appreciate the long-standing wisdom in them, and in this instance, the spring weather was good and this batch was picked very shortly after Hachijuhachiya.

The Miyazakis have a very small operation with around half a hectare of tea bushes, and over fifty years’ experience of making Gyokuro and working their area of land, which means that they don’t need to rely on chemicals to find the umami, sweetness and that deep green colour.

They spilt the production so that Mrs Miyazaki oversees the team of local women who hand-pick the leaves, which even includes getting up at 2.30am to make sure that their lunch is prepared! Hand-picking the tea is extremely rare in Japan nowadays and only the highest quality teas are still hand-picked as opposed to machine picked. This means that the leaves are kept more intact with no coarse stem included, so there is less need for further refining because the correct part of the leaf is selected. Mr Miyazaki oversees the production of the leaves after picking in their on-site wooden workshop. Alongside their tea bushes they are also growing bamboo, tangerines and rice! The shoots from the bamboo and the tangerines are no doubt often enjoyed as part of those lunches – and the rice is used to make the straw which is woven into the tana canopies that shade the bushes.

Once the leaves are hand-picked they are processed very similarly to Sencha, another of our favourite Japanese green teas. First, the leaves are steamed to lock in that forest green colour and enhance the umami and crisp vegetal notes, before being rolled into long, fine spear shapes and lightly dried. The tea might then be tasted for quality and then rested for a few months to mellow before a final refining process sorts the Gyokuro leaves into various grades.

A Note from Tom who made this video as I was writing this:

“I’ve just finished sampling the spring 2020 picked Gyokuro and am pleased to say that from a table of more than 20 teas, Mr & Mrs Miyazaki’s latest batch stood out and was selected. All being well it should be arriving in August!”

What is this batch like to drink?

It is incredibly green and refreshing, but with great umami depth that gives way to a mouth coating sweetness. It’s this lingering sweetness which means that for many they’ll want to keep drinking it sip after sip.

What I love about Gyokuro is the unique aroma – it’s not like any other green tea. The distinct “green” or vegetal notes from the warm leaves always remind me of freshly cut grass and there’s a savouriness that makes me think of a pleasant sea breeze. The colour of the infusion is also unique – it’s a very pale green that is clouded (clarity of the infusion is a mark of quality in almost all teas, but not gyokuro – the high concentration of glutamates and the unique processing mean the infusion goes cloudy). This colour gives a real indication of the thick and almost soup-like texture of Gyokuro.

The flavours that hit you first from the infusion are the more vegetal and grassy notes, like deep steamed spinach and buttery green beans. The texture is very smooth and viscous which accentuates the flavours as they transform, with a complex floral sweetness, balanced by a hint of pleasant bitterness and that all-important umami.

Where and when is this tea for?

Gyokuro is a tea that is best enjoyed slowly and with some focus. It’s not as forgiving in its making as Chinese green teas or even Sencha, so you’ll need a little attention to prepare it well – it’s not complicated though and it does pay off. It’s one of the few teas that I enjoy alongside food too. The depth of the savouriness means that it can complement some rich foods, especially Japanese cuisine. The Miyazakis in fact recommend having some small tea snacks alongside it – the first couple of infusions they enjoy with light pickles and the later infusions with something sweeter, perhaps tangerine segments or a local Japanese cake called Yokan, made of a red bean paste, which goes very well with Gyokuro.