Ujeon, sejak, jungjak and daejak are names you may meet when comparing Korean green tea. They relate to the harvest and leaf, and give you a useful starting point. To choose a particular tea, read the maker's description alongside the name.
Four names, a sequence through the harvest
Descriptions of Korean green tea commonly group these names by the flush or plucking period and leaf size. Ujeon refers to an early harvest; sejak follows with young leaf, while jungjak and daejak refer to progressively later plucks. The names should not be read as a guarantee that every tea in one group tastes the same.
When an exact harvest date matters to your choice, look for a date documented for that product and batch. A general calendar in a guide cannot establish the day on which the leaves in a particular pouch were picked.
What to compare after the grade
Start with the maker, the stated origin and the format. Then look for preparation instructions and tasting notes. Two teas sharing a grade can still be different purchases: their packs may contain different weights, their processing descriptions may differ and one may suit equipment you already own more easily.
Separate a tasting description from the recipe. A maker may use words such as nutty or floral to describe the cup. Check the ingredient list to establish whether other ingredients have actually been added.
Price needs a second number
The ticket price does not tell you the whole comparison. Put pack size beside it. If both products state net weight, compare the price per gram before deciding which costs more. Use a price per prepared cup only when the dose is specified; do not assume every tea uses the same amount.
For a first purchase, think about how much you want to explore. A smaller pack may suit a tasting exercise even when its unit price is higher. A larger pack is only useful if its contents and preparation fit the way you drink tea.
Use the product's own brewing directions
A grade name is not a universal recipe. Begin with the instructions for the selected tea, including the amount, water volume, temperature and time wherever stated. Keep a short note of how you prepared it and what you enjoyed. That gives you a more useful basis for the next cup than changing several things at once.
If an instruction is absent, do not substitute a precise-looking number from another product. Ask for the missing detail, particularly when comparing portioned bags with loose leaf.
A grade does not measure caffeine
Research on green tea has examined differences in composition across leaves and plucking positions. It does not provide a caffeine declaration for every retail tea with the same grade name. For that, use information documented for the specific product and preparation.
Read our caffeine guide if caffeine is part of your decision. To start comparing formats, visit choosing your first Korean tea or the loose-leaf guide.
Sources
- Separations: review including Korean tea classification by flush and leaf size
- Lee et al.: metabolic dependence of green tea on plucking positions
Seoul Rituals editorial team. Updated 13 September 2026.