Sorting

Sorting is the last operation in tea and the one that decides which grade the tea is sold as, which makes it a commercial step as much as a craft one. It is cleaning and sifting: stems, dust and broken leaf out, then whatever remains separated by size. It is also where the finishing operations sit, blending and scenting among them, because both are done to leaf that is otherwise made.

What it is

Separating made tea into what will be sold and what will not, then into grades. Commodity tea passes over vibrating conveyors carrying different mesh sizes, which sift it by particle size: dust, fannings, broken leaf and whole leaf, each sold at its own price. Fine tea is sorted by hand and that hand sorting can be the most labour-intensive part of the entire process. Taking the stems out of wulong costs one person about ten hours per 12 kg and removes roughly a fifth of the weight along with them.

What it does to the leaf

Nothing chemical. This is the one step that does not change the tea, only what ends up in the bag and some growers say plainly that stem removal does nothing for flavour and is done so the tea looks right. That does not make it neutral. Leaf size governs extraction speed, so a graded lot brews consistently while an ungraded one brews unevenly and the smaller the particle the faster and harsher the infusion.

How it's done

Sieves, machines and eyes. Stacked bamboo meshes are the traditional tool and are still used for higher-grade tea. Modern lines run static rollers and mesh. Japan uses optical sorters, where every leaf is scanned by camera and pushed out of the stream by a precise jet of air according to its size and colour. Hand sorting is what fine tea gets and for puerh the maocha is graded one to nine, from the smallest leaf to the largest. Blending rides on the same stage: batches are grouped and blended at the end of Japanese processing, and leaf from different origins is grouped just before a sheng cake is pressed. Scenting sits at the same stage for the same reason, being something done to a tea that is otherwise finished.

What it tastes like

Grade shows up as speed. Fannings and dust give a fast, dark, blunt cup, which is exactly what a teabag needs and why CTC leaf is broken so small. Whole leaf gives up its flavour slowly and holds more aroma. Neither is better in the abstract; they are answers to different questions about how much time you have and what you are going to put in the cup.

What people get wrong

Reading a grade letter as a verdict on the tea. The British grades used in India, Sri Lanka and Kenya describe leaf size and wholeness. Whole leaf is what orthodox production aims at and it does fetch more, but a smaller grade from a good garden beats a whole-leaf grade from a poor one and the letters cannot carry that. The second mistake is expecting the vocabulary to be universal. China does not use it, describing a tea by name, place and pluck instead.

Where the boundary blurs

Calling this the last step holds for most tea and not for all. Fresh leaf is often picked over right after plucking, ripe puerh is sorted after the pile to remove leaf that did not take and sheng is sorted and grouped before it is pressed rather than after. In a pressed tea the sorting sits in the middle of the sequence, which is also where a recipe cake gets its recipe: the grouping of leaf from different origins is a blending decision made at the sorting bench.

Styles where this step is distinctive

and 13 more

teabert, the tealytics teapot, keeper of the kettle

Grade tells you leaf size, not quality. Tip the dry leaf onto a white plate and look at it; that says more than the letters do.

Sources

sorting is the last step in tea production and covers cleaning and sifting; commodity tea is sifted by vibrating conveyors with different mesh sizes into dust, fannings, broken leaf and whole leaf, while higher-end tea is sorted by hand Gebely, Tea: A User's Guide (2016), ch. 4
removing the stems from wulong takes one person ten hours per 12 kg and leaves 9.4 kg behind; some growers hold that it does nothing for the flavour and is done for appearance Gascoyne et al., Tea: History, Terroirs, Varieties (2014), 'Processing Green Wulong Teas'
Japanese sorting uses static rollers and mesh or optical scanners that scan each leaf and separate it by a high-precision air jet, and batches are grouped and blended at the final stage; sheng puerh maocha is sorted into nine grades from smallest leaf to largest, with leaf from different origins grouped before compression Gascoyne et al., Tea: History, Terroirs, Varieties (2014), 'Processing Japanese Green Teas' and 'The Processing of Chinese Teas'
leaves that break are ranked using the British grading system in India, Sri Lanka and Kenya and priced accordingly, while whole unbroken leaf is the aim of orthodox production Gaylard, The Tea Book (DK, 2015), 'The production process'
fresh tea leaves are sorted soon after picking to remove rotten or fragmented leaves and separate grades, and the maocha is sorted again before fine processing Zhang, Puer Tea: Ancient Caravans and Urban Chic (2014), appendix 1