I bought a big bag to save money and it was stale before I finished it

In short

The unit price falls with quantity and the rate of deterioration does not, so beyond a certain size the cheaper tea costs more per drinkable cup. Which size that is depends almost entirely on category, and green tea and black tea sit at opposite ends of it.

Likely causes, in order

Most likely first. Answer the question under each one before moving on — several of these look alike in the cup and are told apart only by what was done to the leaf.

1. 1. The category was the wrong one to buy in bulk

   Leaf quality

   Check: Was it green tea or matcha, rather than a black tea, a roasted oolong or a dark tea?

   Fix: Green tea and matcha fade fastest of anything in the catalogue, losing aroma and sweetness while astringency stays. Buy those in the smallest quantity you will actually drink in a season. Black, roasted and dark teas tolerate large purchases; buy in bulk there instead.

2. 2. One large container opened repeatedly

   Storage

   Check: Have you been opening the same big bag every day for months?

   Fix: Every opening exchanges the headspace and the leaf is exposed to it again. Decant into several small containers on the day it arrives and open only one. This single habit is worth more than any container upgrade.

3. 3. The bag was never a storage container

   Storage

   Check: Was it a paper or plain plastic bag, or a foil pouch that has been folded rather than resealed?

   Fix: Paper and plain plastic pass air and water vapour. A foil laminate pouch, air squeezed out and properly resealed, is the effective cheap option; a plain bag inside a tin is better than either alone.

4. 4. Freezing was tried and made it worse

   Storage

   Check: Did you freeze it and take it in and out?

   Fix: Cold storage is a real professional practice and it is unforgiving at home: every removal condenses moisture on cold leaf. If tea has been frozen it must be brought to room temperature sealed, before opening, and ideally opened once. Repeated cycles do more harm than the shelf would have.

5. 5. It was fine and the comparison is with something newer

   Leaf qualityInferred by TeaHQ, not established

   Check: Did it start tasting stale immediately after you opened a fresh packet of the same tea?

   Fix: Gradual fading is very hard to notice and obvious the moment a fresh reference arrives. That is a real observation, and the honest conclusion is about purchase size next time rather than about this bag.

Tea types this applies to

• Green tea

Related problems

Sharing a cause category, a tea type or a brewing method with this one.

• My matcha powder has gone dull green or khaki — The powder that was vivid green when the tin was opened is now olive, khaki or faintly brown, and the bowl looks muddy rather than bright.
• My tea goes damp within weeks and I live somewhere humid — Leaf that arrived loose and crisp becomes soft, slightly clumped and quiet within a few weeks, and the aroma flattens long before any best-before date is close.
• I have too many teas open and most of them are going stale — A dozen or more packets are open at once, three or four get drunk regularly, and the rest fade quietly on the shelf until they are thrown away.
• My Japanese green tea tastes of seaweed or fish — A sencha, gyokuro or matcha reads as marine — seaweed at best, distinctly fishy at worst — and it is not clear whether that is the tea or a fault.
• My matcha is harsh and I think it is a cooking grade — A matcha bought to drink is dull-coloured, gritty and aggressively bitter, and the tin says culinary, cooking or ingredient grade — or says nothing at all.

Sources