This document is a proposed standard for evaluating tea quality in hopes to get people serious about evaluating their tea on the same page. Updated April 7, 2016.
Provide a standard preparation method for tea evaluation.
Provide a standard for measuring leaf quality for both dry and steeped leaf.
Provide a hierarchical standard nomenclature for describing tea flavors.
Provide a standard nomenclature for describing the color of steeped tea (coming soon).
Before You Begin
Make sure you have clear testing goals in mind and be sure you have cleared your palate.
Section 1: Standard Preparation Methods for Tea Evaluation
It is advisable to prepare each tea to be evaluated using two methods, the first is a veritable “trial-by-fire” that is commonly used in tea evaluations in the tea industry and is based on the ISO-3103 specifications for tea evaluation. The second is an attempt to simulate the preparation methods subjected to each tea by average consumers.
This method involves a long steep time in near-boiling water, however the ratio of water to dry leaf is very low compared to many other suggested steeping parameters. The idea here is to steep the leaves long and hot in hopes of bringing out as many characteristics as possible for evaluation. If evaluating many teas or setting up a tea tasting room or program, use the same water across all of your tests. As with any tests like this, the object is to have only one variable changing between tests and in our case, it’s the tea that will be changing.
– 2 grams (0.07 oz) of tea per 100ml (3.38 fl oz) boiling water in steeping vessel
– brewing time: 6 minutes
– steeped tea is then strained into a separate vessel
It is important that the same type of vessel be used for all tests. ISO3103 also covers specifications for a standardized tasting vessel (seen below). If test results will be compared to others in another location, it is advisable that everyone be using the same vessel for preparation.
What to note:
1.What color is the liquor?
2. What does the liquor smell like?
3. What does the liquor taste like?
While the trial-by-fire method is useful for evaluating the quality of a tea, it is also helpful to emulate the preparation methods that are most likely to be used by consumers. For this preparation method, we’ll use different parameters for each tea type.
Time for First Steeping
– 3g (0.11 oz) of tea for 235ml water (8fl oz)
Again, it is important to use the same vessel and water across multiple tests.
What to note:
1.What color is the liquor?
2. What does the liquor smell like? (How does it change from steep to steep?)
3. What does the liquor taste like? (How does it change from steep to steep?)
4. How many steepings can the tea withstand and still produce acceptable flavor?
Section 2: Leaf Quality
When evaluating leaf quality, it is important to look at both the dry leaves and the steeped leaves. Each will provide clues to the overall quality of the tea.
What to note about dry leaf:
What color are the dry leaves?
Recognizing quality by color will come with experience. Once you have cupped many teas, you will begin to recognize patterns in tea types and eventually tea styles. For example, if a farmer/merchant tells you that a tea is a green tea but the color is more yellow or brown, you should note this as the off color could mean an insufficient fixing phase for the green tea, improper storage, or it could just mean that the tea is old.
What shape are the dry leaves?
Recognizing quality by shape will also come with experience. Once you have cupped many teas, you will begin to recognize patterns in tea types and eventually tea styles. For example, if a farmer/merchant tells you that a tea is a half ball-style oolong yet it is loosely rolled and looks more like a strip style oolong, you would associate this tea as a low-quality oolong.
What size is each dry leaf? (length of longest side in mm)
Leaf particle size is a sign of quality. I say particles here because we are dealing with all teas, those that may be ground into the tiniest of particles to those that are full leaves. When evaluating many teas, it is often helpful to group them by particle size as a CTC tea will not easily compare to a full-leaf tea. For your records, it is helpful to measure the length of the longest size of a few tea particles in mm for comparisons year to year or batch to batch.
Are the leaf particles pristine?
Consistent leaf particle size is a marker of quality. Consistent leaf particles will steep at a similar rate as they have a comparable surface area exposed to water while steeping. Consistent leaf particles may also indicate hand plucked tea and careful, delicate processing methods. Broken, inconsistent leaf particles and the presence of crumbs can indicate machine plucking and handling during processing and is a sign of a lower quality tea.
What to note about steeped leaf:
What color are the steeped leaves?
Can you discern the plucking standard from the steeped leaves? (how many leaves? bud included? only buds?)
How many leaves are there in each “piece” of steeped finished tea?
Are any of them broken? Can you discern machine vs. hand plucked?
Are any of the leaves bitten by insects?
Is the color of the leaves consistent?
How much of the leaves have been oxidized? If an oolong, are the edges red?
Section 3: Standard Nomenclature of Tea Flavors
It is important when more than one individual is describing the flavor of a tea that they use a standard nomenclature for their descriptions and note the intensity of each term on a scale from 1-5.. This standard nomenclature is presented hierarchically and should represented as such in final descriptions. Here is the recommended notation:
Top level::Second Level::Third Level (Intensity)
Example for a First Flush Castleton Estate Darjeeling tea:
Fruit :: Dry Fruit :: Raisin (3)
Here are the top level terms in the nomenclature:
Vegetal / Animal / Sea / Mineral / Char / Sweet / Fruit / Dried Fruit / Floral / Spice / Earthy / Nutty
Here is the expanded list of terms in the nomenclature:
Earthy::Wood::Fresh Cut Wood
Fruit::Tree Fruit::Green Apple
Fruit::Tree Fruit::Red Apple
Vegetal::Grass::Fresh Cut Grass
Vegetal::Grass::Straw / Hay
Here is a list of modifiers for terms in the above nomenclature:
Cooked, fresh, rotten, old, stale, burnt.
Here is a list of terms used to describe mouthfeel / body / texture:
Smooth, buttery, flowing thick, watery, oily, astringent, robust, unctuous, structured, silky, mouth-filling, supple, rounded, powdery, velvety, creamy, flat, dull, bright, brisk.