usucha (thin matcha)
ingredient / ingredient-usucha
薄茶
Usucha (thin matcha) is a lower-concentration method of preparing matcha, and the tea so prepared, in which matcha is whisked with less tea powder and more hot water than koicha.
On this page (6 sections)
Reading the bitterness
Usucha is a way of preparing matcha at a lower concentration than koicha, using less matcha and more hot water, and also refers to the tea itself. A personal class website run by an Omotesenke instructor explains that it uses about one and a half chashaku scoops of matcha and about 50–60 ml of hot water, and that in the Omotesenke style it should not be whipped too much. This is an approximate amount given by an individual class.
In research on the motion of preparing matcha, the whisking of 4 skilled subjects was analyzed under conditions of 2 g of matcha, 70 mL of water at 80°C, and a tea bowl with an inner diameter of 10.5 cm. Subject A, whose finish was good, is presumed to have whisked at a high initial rate of about 8 times per second and produced fine bubbles. This research's main focus is motion analysis, not an evaluation of taste.
A study that examined the taste components of matcha found that, with a preparation method of vigorously whisking with a chasen (tea whisk), the extraction rate of theanine, caffeine, and EGC exceeded 80%, while EGCG, which has a strong bitter-astringent taste, did not reach 50%. The study considered this to result from a rapid drop in water temperature hindering the elution of EGCG, which is highly temperature-dependent, and gave this as the reason the infusion does not show as much bitter-astringent taste as would be expected from the amount of these components in the tea leaves.
In the taste terminology used for matcha judging, bitterness is treated as a defect related to the grinding method or storage condition. Over-milling causes tea leaves to linger inside the stone mill, extending the heating time, which can produce a firing taste accompanied by bitterness. This is an item checked using a judging method that whisks at a low concentration close to usucha (2 g matcha to 100 mL hot water).
Sources for this overview
Checked for this overview: Matched, as an approximate amount from a personal class website run by an Omotesenke instructor, one and a half chashaku scoops, 50–60 ml, and the point about not whipping too much.
Checked for this overview: Matched 2 g of matcha, 80°C, 70 mL of water, an inner diameter of 10.5 cm, 4 skilled subjects, about 8 times per second, and the limitation of the research.
抹茶の点て方に関する化学的考察 (Chemical research on the preparation of matcha)
Checked for this overview: Used for the extraction rate (theanine, caffeine, and EGC 80% or higher; EGCG 50% or lower) and the discussion of EGCG elution being suppressed by the drop in water temperature
抹茶の審査について (Sensory Evaluation of Matcha)
Checked for this overview: Used for the definition of bitterness as a taste defect term, the explanation of the cause via over-milling, and the judging conditions (2 g, 100 mL)
Other names: usucha (ja)
Structured claims — open a section to read each claim's confidence, evidence and limits
Sensory (1)
Scope: An explanation of the matcha review method (taste evaluation using 2 g sample, 100 mL hot water, chasen stirring to raise foam; Table 6, taste terminology)
Show data
ingredient-usucha —has_perceived_bitterness_associated_with→ "In the terminology used for the taste review of matcha (a method pouring 100 mL of hot water onto a 2 g sample and stirring with a chasen to raise foam), bitterness is positioned as a defect term that can become stronger due to over-milling, deterioration, and the like."How processing and cooking change it (2)
Scope: Omotesenke (an explanation by an individual class), and conditions set in motion-analysis research.
Note: Note that the suggested amount on the class website (number of chashaku scoops and mL) differs in nature from the conditions set in motion-analysis research not intended for sensory evaluation (specified in g, mL, and ℃). Do not treat them as a single unified standard.
Show data
ingredient-usucha —has_reported_preparation_style_of→ "According to the explanation on a class website by an Omotesenke instructor, 「藤本薫里」 (Fujimoto Kaori), usucha is described as prepared with about 1 and a half chashaku scoops of matcha and about 50〜60ml of hot water (in the Omotesenke school, it is not whipped too much). In one example of conditions used for motion-analysis research, 2g of matcha and 70mL of water at 80℃ were used."Scope: Matcha infusion prepared according to the method used in sensory review; component analysis by capillary electrophoresis and high-performance liquid chromatography (2018 Japan Society of Cookery Science conference abstract)
Show data
ingredient-usucha —has_perceived_bitterness_suppressed_by→ "In a preparation method where matcha is whisked vigorously with a chasen, the extraction rate for theanine, caffeine, and EGC prepared according to the review's whisking method was above 80%, whereas for EGCG it remained below 50%, and the EGCG concentration in the infusion was lower than in sensory-review infusions of sencha and other teas. It was discussed that whisking the chasen vigorously causes a sharp drop in water temperature, and this hinders the highly temperature-dependent dissolution of EGCG into the water, so that the infusion does not show as strong a bitter-astringent taste as would be expected from the content in the tea leaf."