Coffee bean storage

Coffee bean storage is a broad term describing the packaging and preservation of coffee beans throughout the process from harvesting to brewing. Although the term is applicable to many phases of this process, it is typically applied to ideal home storage for maximum consumer coffee enjoyment.

Green coffee

After the cherries are put through the pulper and the seeds have been soaked, they are set out to sun-dry for a period of one week. The beans are periodically raked to ensure even drying. Once dried, the beans will form a thin, paper-like shell called parchment. Once formed, the parchment will increase the beans’ storage life considerably^[1]. When the beans are ready, the parchment is removed, and the beans are graded and sorted according size, weight and defects. The sorted beans are then stored in 60 or 70 kg sacks called sisal bags that help the beans retain moisture for a longer period of time.^[2] The storage time cannot exceed one year for the beans to be considered a current crop. If the green coffee remains in storage for longer than a year, it is considered old crop, and is less valuable because of its drier state^[1].

Roast coffee

Once a coffee bean is roasted, it is either packaged immediately for sale, or ground and then packaged for sale. Packages used are typically either an airtight plastic container or vacuum-sealed wrapping, or a folded-over bag with a two-way air valve. Each type of package has its own advantages. While the airtight containers allow maximum freshness of the bean, and prolong the shelf life of the product, the valve allows the customer to smell the coffee before purchase and discern the quality and type of the blend.

Home storage

Once bought, the method of storage used depends on the type coffee purchased. Green beans store the best in cooled airtight containers, and can easily last in this state for a year without losing flavor^[3]. Roasted whole beans are best stored in airtight containers out of the light. The best material choices for the container are ceramic, or opaque glass. Plastic and metal will alter the flavor of the coffee bean.^[3] In addition, for the first week of storage, containers should be opened to vent out the carbon dioxide gas that will be produced by the roasted beans to prevent the gas from changing the quality of the coffee.ref name='CTS' /> Whole bean roasted coffee stored in this manner will last for about two weeks. If the beans are frozen, however, the flavor can last for around a month. Refrigeration alone will not achieve the same effect on the storage life of the bean. Once beans are frozen, leaving them frozen until brewing best preserves the flavor of the coffee. Frozen beans will grind the same as unfrozen beans, but refreezing beans alters the quality of the coffee.^[3] Coffee grounds are stored in airtight ceramic or glass containers, like roasted beans. Due to increased total surface area of coffee grounds, the grounds go stale in days, rather than weeks. In addition, freezing has no effect in increasing the storage life of coffee grounds.^[3]

References

1. ^ ^{a b} Les Drent, "Coffee Farming in Kona, Hawaii", "Coffee Times", retrieved 2/2011
2. ^ Douwe Egberts, "Coffee Development - From Bean to Cup", "Hollandbymail.com", retrieved 2/2011
3. ^ ^{a b c d} Sean Paajanen, "Proper Coffee Storage", "About.com", retrieved 2/2011