View source for Gyokuro

{{Short description|Japanese shaded green tea}}
{{Italic title|reason=[[:Category:Japanese words and phrases]]}}
{{Infobox Tea
| Tea_name = Gyokuro
| Tea_type = [[Green tea|Green]]
| Tea_color = Green
| Tea_image = [[File:Gyokuro img 0067.jpg|200px]]
| Tea_origin = Japan
| Tea_names = 玉露, jewel dew / jade dew / pearl dew / precious dew
| Tea_quick = 
}}
{{nihongo|'''''Gyokuro'''''|[[wikt:玉|玉]][[wikt:露|露]]|lead=yes|extra="jade dew"}} is a type of [[green tea]] from [[Japan]]. It differs from the standard ''[[sencha]]'' (a classic green tea grown in the sun) in being grown under the shade rather than the full sun.<ref name="myjapanesegreentea">{{cite web |title=Gyokuro |url=https://www.myjapanesegreentea.com/gyokuro |website=www.myjapanesegreentea.com}}</ref> The name "gyokuro" translates as "jewel dew" (or "jade dew").<ref>{{Citation |title=ぎょくろ |date=2018-10-16 |url=https://en.wiktionary.org/w/index.php?title=%E3%81%8E%E3%82%87%E3%81%8F%E3%82%8D&oldid=50497091 |work=Wiktionary |language=en |access-date=2022-10-26}}</ref> According to the Japan Tea Central Association, gyokuro is defined as "a tea manufactured in the same manner as sencha from tea leaves picked from covered tea gardens that are almost completely shaded from sunlight for about 20 days using covering materials such as reed screens, straw, or shading nets, from the time when the new shoots of the first flush start to grow."<ref name="hyoujikijyun">{{Cite web |title=緑茶の表示基準 |url=https://www.nihon-cha.or.jp/pdf/hyoujikijyun.pdf |accessdate=2022-06-13 |publisher=公益社団法人日本茶業中央会}}</ref>

While most sencha is from the {{nihongo|Yabukita|薮北}} [[cultivar]] of ''[[Camellia sinensis]]'', gyokuro is often made from a specialised variety such as Asahi, Okumidori, Yamakai, and Saemidori. Most gyokuro is grown in the [[Fukuoka Prefecture|Fukuoka]], [[Kyoto Prefecture|Kyoto]], and [[Mie Prefecture|Mie]] prefectures.

Gyokuro tea production dates back to the 1830s, when the merchant [[Yamamoto Kahei]] discovered some Japanese farmers were covering tea plants with a netting to protect them from frost, and that this actually changed the flavour and aroma of the tea. He introduced the tea to Edo and it was immediately popular.<ref>『山本山の歴史』78頁</ref>

== Cultivation and processing ==
[[file:Tee-beschatet-gross.jpg|thumb|Gyokuro with a scaffold ready to be deployed for shading]]
Though it is categorised as a type of [[sencha]] according to production methods, gyokuro cultivation differs from other sencha teas. Gyokuro tea leaves are shielded from the sun before being harvested. The period can vary from twenty to thirty days. Three weeks / twenty days is a standard length of time for a tea to be considered gyokuro proper.<ref name=":0">Brekell, Oscar. ''Beginner's Guide to Japanese Tea: Selecting and Brewing the Perfect Cup of Sencha, Matcha, and Other Japanese Teas,'' p. 22. Tuttle Publishing, Dec 7, 2021.</ref><ref>{{Cite web |date=2024-04-05 |title=Gyokuro Tea Complete Guide {{!}} Nio Teas ® |url=https://nioteas.com/blogs/gyokuro/gyokuro-tea |access-date=2024-06-05 |website=Nio Teas |language=en}}</ref><ref name="myjapanesegreentea" /> Anything shaded for under twenty days is considered [[Kabuse tea|kabuse]] tea.<ref name=":1">Heiss, Mary Lou; Heiss, Robert J. ''The Story of Tea: A Cultural History and Drinking Guide'', p. 182-183. Clarkson Potter/Ten Speed, Mar 23, 2011.</ref>

The shading causes both the [[amino acid]] [[L-theanine]] and the [[alkaloid]] [[caffeine]] in the tea leaves to increase, and the [[catechins]] and [[tannin]]s to decrease, which yields significant differences from the flavour of sencha.<ref>{{cite web |title=Components of Gyokuro｜ IPPODO |url=https://www.ippodo-tea.co.jp/en/tea/gyokuro_02.html |url-status=usurped |archive-url=https://web.archive.org/web/20210512005545/https://www.ippodo-tea.co.jp/en/tea/gyokuro_02.html |archive-date=2021-05-12 |website=www.ippodo-tea.co.jp}}</ref> The shading causes the plant to stop converting theanine into catechins to protect itself from UV light.<ref name=":0" /> Furthermore, the stress of shading also makes the plant produce more [[caffeine]] to protect itself. Gyokuro also has higher [[chlorophyll]] content, which accounts for the dark green colour of the leaves. These chemical differences lead to unique flavour and aroma of the tea, giving it more [[umami]], a savory sweetness, and less [[Bitterness (taste)|bitterness]] and [[Astringent|astringency]]. The increased L-theanine content elicits the increased [[umami]] taste of gyokuro.<ref name="pmid24633359">{{cite journal |vauthors=Narukawa M, Toda Y, Nakagita T, Hayashi Y, Misaka T |date=June 2014 |title=L-Theanine elicits umami taste via the T1R1 + T1R3 umami taste receptor |journal=Amino Acids |volume=46 |issue=6 |pages=1583–1587 |doi=10.1007/s00726-014-1713-3 |pmid=24633359 |s2cid=17380461}}</ref> It also produces a calming effect which balances out the high caffeine content of gyokuro.<ref>Brekell, Oscar. ''Beginner's Guide to Japanese Tea: Selecting and Brewing the Perfect Cup of Sencha, Matcha, and Other Japanese Teas,'' p. 17. Tuttle Publishing, Dec 7, 2021.</ref> Studies on L-theanine indicate that it may also help reduce stress and anxiety and may have [[Neuroprotection|neuroprotective]] effects.<ref name="pmid31758301">{{cite journal |display-authors=3 |vauthors=Williams JL, Everett JM, D'Cunha NM, Sergi D, Georgousopoulou EN, Keegan RJ, McKune AJ, Mellor DD, Anstice N, Naumovski N |date=March 2020 |title=The Effects of Green Tea Amino Acid L-Theanine Consumption on the Ability to Manage Stress and Anxiety Levels: a Systematic Review |url=https://publications.aston.ac.uk/id/eprint/41068/1/Green_Tea_Amino_Acid.pdf |journal=Plant Foods for Human Nutrition |volume=75 |issue=1 |pages=12–23 |doi=10.1007/s11130-019-00771-5 |pmc= |pmid=31758301 |s2cid=208213702}}</ref><ref name="nathan">{{cite journal |vauthors=Nathan PJ, Lu K, Gray M, Oliver C |year=2006 |title=The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent |journal=Journal of Herbal Pharmacotherapy |volume=6 |issue=2 |pages=21–30 |doi=10.1300/J157v06n02_02 |pmid=17182482}}</ref><ref name="pmid15207710">{{cite journal |vauthors=Nagasawa K, Aoki H, Yasuda E, Nagai K, Shimohama S, Fujimoto S |date=July 2004 |title=Possible involvement of group I mGluRs in neuroprotective effect of theanine |journal=Biochemical and Biophysical Research Communications |volume=320 |issue=1 |pages=116–122 |doi=10.1016/j.bbrc.2004.05.143 |pmid=15207710}}</ref>

The length and type of shading or covering ([[Kabuse tea|kabuse]]) will affect the taste of the gyokuro tea. Shading may be done with a scaffolding built over the tea field or by covering the plants directly with the shading material (jikagise).<ref name=":1" /> The opacity of the shading material (which can be synthetic, straw, or reed) will also affect how much theanine is contained in the leaves, which affects the flavour, particularly umami. The process is often done in stages, initially blocking 70% of the sunlight, and ramping up to 80 and 90 percent before harvesting. The higher grades of gyokuro are shaded more extensively and for longer times.<ref name=":1" />

The processing of the picked gyokuro leaves will also affect the aroma and taste of the tea. Like standard sencha, gyokuro is steamed after harvesting, usually in industrial machinery. The length of the steaming can be short (asamushi), middling (chumushi), or long (fukamushi, 1–2 minutes). This will also affect the aroma and flavour of the tea. After steaming, the leaves are then dried and rolled, traditionally by hand, but now it is common to use industrial machinery to roll the leaves.  [[file:The-IMG 0016.jpg|thumb|[[Karigane (tea)|Karigane]] made from gyokuro, the lighter coloured stems are visible]]
If the leaves were harvested mechanically, the stems and other parts of the plant must be separated out from the leaves. Hand picked gyokuro exists, but it commands higher prices.

The stems, stalks, twigs and other by-products of gyokuro processing may be used to make a higher end [[kukicha]] (twig tea), which is called ''karigane'' or ''shiraore'' when processed from gyokuro stems and parts.<ref>{{cite web |title=The Ultimate Guide to Kukicha and Karigane |url=https://japanesetea.sg/japanese-tea-pedia/kukicha-and-karigane/ |access-date=2022-02-02}}</ref> These parts have a high concentration of theanine due to their lower photosynthetic activity compared to the leaves, have less caffeine, and also contain different aromatic and flavourful compounds, making their flavour distinct from standard gyokuro. A rough unprocessed mix of gyokuro leaves, broken particles, stalks and stems, is also sold separately as unprocessed tea / unrefined tea ([[aracha]]). These rougher types of gyokuro tend to be less expensive than standard leaf only gyokuro.

==Brewing==
[[File:Japanese traditional tea by yomi955 in Kyoto.jpg|thumb|Gyokuro brewed in a traditional [[Kyūsu]] teapot]]

Brewing gyokuro is generally done with lower temperature water (between 40 and 70 [[celsius]]; 104 to 158 [[fahrenheit]] depending on the leaf and personal preference). The traditional Japanese method of brewing gyokuro uses a high water to leaf ratio, usually around 5 grams of leaves for 150 millilitres of water. Since the leaves are tightly rolled and need time to open, the infusion time is usually longer than other green teas (2 minutes). After the leaves have opened, the same gyokuro can then be re-infused three or four more times for 20–30 seconds.

In the practice of ''[[Senchadō]]'' (the way of sencha), many schools use a "two-step brewing" method. First, low-temperature water, cooled by initially pouring it into a separate cooling vessel, is used to extract sweetness. Then, high-temperature water is used to extract bitterness. There are also schools that add a "three-step brewing" method, which use water of intermediate temperature for the second infusion to extract astringency. However, due to the increased time required for each session and the fact that the components may be almost fully extracted by the second infusion for some tea leaves, the "two-step brewing" method is more prevalent at large tea gatherings. Small teapots such as koburi or houhin (small teapots without a handle) are often used, and the tea bowls are also smaller compared to those used for sencha.

== Regions and market ==
More than 40% of gyokuro is produced in [[Yame]] ([[Fukuoka Prefecture]]), and in the national tea jury in August 2007, [[Yamecha]] (Yame tea) held all the ranking positions from first to 26th as the best gyokuro.<ref name="tea-jury07">[http://www.pref.shiga.jp/g/nosan/teafestival/shinsakekka/kekkaitirangyoku.pdf Result of 2007 National Tea Jury] {{webarchive|url=https://web.archive.org/web/20110515172924/http://www.pref.shiga.jp/g/nosan/teafestival/shinsakekka/kekkaitirangyoku.pdf|date=May 15, 2011}} {{in lang|ja}}</ref> A high amount of [[Uji tea|Ujicha]] gyokuro is also produced around [[Uji, Kyoto|Uji]], in the [[Kyoto Prefecture|Kyoto prefecture]] (140 [[ton]]s in 2008).<ref name=":2">{{Cite web |title=20年産工芸農作物の収穫量（全国農業地域別・都道府県別・主産県別） - 茶 - 茶期別・茶種別荒茶生産量（主産県別）- 年間計 |url=https://www.e-stat.go.jp/SG1/estat/GL71050103.do?_xlsDownload_&fileId=000003606381&releaseCount=3 |accessdate=2014-09-21 |publisher=農林水産省}}</ref> In 2008, the production volume of gyokuro in [[Mie Prefecture]] increased more than 40 times compared to the previous year (132 tons in 2008, 3 tons in 2007).<ref name=":2" />

Gyokuro is one of the most expensive types of sencha available in Japan.<ref name="myjapanesegreentea" /> The name was originally the product name of the tea made by [[Yamamotoyama (tea company)|Yamamotoyama]]. The tea was first discovered by Yamamotoyama's sixth owner, Yamamoto Kahei, in 1835 ([[Tenpō]] year 6).<ref>{{Cite web |date= 12 July 2022|title=Gyokuro tea |url=https://nioteas.com/blogs/gyokuro/gyokuro-tea |website=nioteas.com}}</ref> The process was completed by another manufacturer at the start of the [[Meiji period]].{{Citation needed|date=October 2020}}

==See also==
* [[Green tea#Japanese green tea|List of Japanese teas]]
* [[Theanine]], a [[nootropic]] extracted from Gyokuro
* [[Tea Culture in Japan]]

==References==
{{Reflist|30em}}

{{Japanese food and drink}}
{{Teas}}

[[Category:Japanese green tea]]
[[Category:Japanese cuisine terms]]