Choose and store green coffee well
Green coffee is the dried seed that becomes brown and aromatic in the roaster. It lasts far longer than roasted coffee, but it is not inert: heat, moisture exchange, oxygen, time, and poor packaging can flatten or damage it.
A listing offers clues rather than promises. Origin, variety, process, altitude, harvest information, and seller notes help form a hypothesis. Your roast and tasting decide whether the coffee suits you.
Reviewed 9 September 2026
Read the clues, not stereotypes
Washed coffees are often described as clean; natural and honey processes may emphasise fruit, sweetness, or body. These are broad tendencies with many exceptions. Country and altitude provide context, not a flavour or quality guarantee.
Varieties can show tendencies without tasting identical everywhere. Canephora, commonly called robusta, generally contains more caffeine than arabica and ranges from commodity to fine quality. Screen size describes physical size, not flavour quality.
Seller notes reflect a particular sample roast and brew. Look for useful traceability, a lot identifier, and harvest or arrival information, then treat flavour notes as an invitation to test rather than a promise.
Buy enough to repeat
Choose an affordable, well-described lot a supplier recommends for your machine and brew style. Balanced washed coffees are common suggestions, but no country or process is automatically easy.
Buy enough for several batches. One kilogram may suit a small machine; larger batches may justify more. Repetition makes equipment changes easier to understand. ‘Current crop’ is not a precise freshness guarantee because harvest calendars, transport, and storage differ.
Control moisture exchange
Properly dried green coffee is commonly near 10 to 12 percent moisture, though water activity better indicates microbial stability. At home, seek a cool, dark place with stable conditions and protection from humidity and strong odours.
Keep coffee in its original barrier liner or a clean, food-safe, well-sealed container. Hermetic packaging limits moisture and oxygen exchange and has outperformed permeable jute in controlled studies, particularly in humid conditions. Paper, cloth, and unlined jute let the beans exchange moisture and odours with the room.
Sealing coffee that is already too wet does not make it safe. If beans have visible mould, were wetted, or smell musty, contact the supplier or discard them rather than hoping roasting will make them safe.
Freezing is optional
Stable room temperature is adequate for coffee used within months. Avoid hot sheds, concrete floors, and large humidity swings. Refrigeration is awkward because repeated opening invites condensation and food odours.
Freezing can preserve valuable coffee when done carefully. Portion dry coffee into moisture-barrier bags, seal them, and keep each bag closed until it reaches room temperature. Evidence is less extensive than for ambient hermetic storage, so freezing is an optional long-term method, not a requirement.
There is no universal twelve-month expiry. Packaging, environment, processing, and initial condition determine ageing. Track the lot and taste over time; buy quantities you can enjoy before the coffee becomes faded, woody, or papery.
Common questions
How long does green coffee last?
There is no fixed flavour expiry. Cool, stable, hermetic storage can keep properly dried coffee useful for a year or longer; permeable packaging in heat or humidity can age much faster.
Should green coffee be airtight?
Properly dried coffee generally benefits from hermetic or high-barrier packaging because it limits moisture and odour exchange. Sealing coffee that is already wet does not make it safe.
Can I freeze green coffee?
Yes. Portion it into sealed moisture-barrier bags and let each still-sealed portion reach room temperature before opening. It is most useful for valuable coffee kept long term.
Sources and further reading
These references support the technical claims above. Practical recommendations are identified as starting points because coffees and equipment differ.
Put this batch to work.
Percolate connects green stock, roast observations, blends, and tastings. Use it when you want the last cup beside you while you plan the next roast.
Start roasting