Coffee Bean Storage & Freshness
How to Buy Fresh Beans and Keep them that Way
On this page…
1. Intro
2. Freshness Test
3. Buying Fresh
4. Storage Tips
5. Links
Updated Jan 2006
Many people new to coffee do not realise just how significant the taste difference is between coffee that is a week or two old, and fresh roasted coffee. It can be quite staggering and if you have ever tried coffee cupping, you will be convinced that buying fresh roasted beans and grinding them yourself is well worth the effort. Also well worth the effort is learning about coffee bean storage and the best ways to keep beans fresh..
Coffee Freshness is determined by the time since roasting, as opposed to when the beans were harvested. In the right conditions, coffee beans will keep for years until they are roasted. Once roasted however, the flavorsome coffee oils are brought to the surface of the bean and will deteriorate and rapidly become rancid. Also after roasting, coffee beans produce coffee gasses (mostly carbon dioxide) for a little over week, with most of the gasses being released in the first 2-3 days. Once the gasses have been completely released, the coffee is stale. The method of coffee bean storage you use can delay this deterioration.
The two main enemies of freshly roasted coffee are oxygen and moisture. In order to reduce moisture contact with the beans you should make sure your supplier uses air to cool the beans after roasting. Some suppliers will quench the beans with water to cool them. This is undesirable as it can leave residual moisture on the beans. In order to reduce the oxygen contact with the beans, suppliers should use nitrogen-flushed bags that are fitted with a one-way valve. Nitrogen is an inert gas, so it will not react with your coffee beans in any way. It is used to displace all the oxygen from the bag before it is sealed. The valve allows the coffee gasses from the roasted beans to escape from the bag without letting oxygen in. This is the best method of coffee bean storage because it keeps the beans dry and oxygen-free (at least until the bag is opened). Also, keeping your beans in a cool, dark place will counteract the negative effects of heat and light.
How to tell if Beans are Fresh
Freshness Test - You've just bought some beans from a new supplier and you're wondering whether they're as fresh as you were led to believe. If you're not sure, there's an easy way to tell. Just place a handful of the beans in a plastic bag, squeeze out all the air and seal the bag with a knot (or perhaps use a zip-lock bag). Leave the bag sealed until the next day. If the beans are freshly roasted, as you have been told, then the bag will be puffed up from the coffee gasses. If the beans are very freshly roasted, the bag may even burst. If, on the other hand, the bag remains flat, then the beans are not producing any more coffee gasses. This indicates that it has been over a week since the beans were roasted.
Other Freshness Indicators - here are some of the things you should look for when buying beans as signs that they are freshly roasted:
- Minimal Surface Oil - (article update 31-Jan-2006)This article previously stated that freshly roasted beans will have a glossy shine due to the oils still sitting on the surface of the bean. This is actually not completely true. The amount of oil on the surface of freshly roasted beans depends on the degree of the roast. Light-to-medium roasts will appear matt and almost no oil will be apparent. Dark roasts will have tiny specks of oil on the surface of the bean… and the darker the roast, the more oil. If the beans are very shiny (wet-look), this is an almost certain sign that the beans are old. They are old enough for all the oils to have made their way to the bean’s surface. To confirm your suspicions, breathe in the aroma. A sour or cigarette-like aroma confirms the beans are stale. A wonderful, sweet toasted-caramel aroma proves the beans are delightfully fresh!
- Wonderful Aroma - the aroma of freshly roasted beans is wonderfully thick and intense. If you can't smell the aroma of the beans wafting out from the shopping bag as you're driving home, then they aren't fresh.
- Frothy Brew - known as the bloom, the coffee gasses released from freshly roasted beans will cause your brew to froth as you pour on the water.
- Full Flavor - freshly roasted coffee will have a full, complete flavor. If your coffee tastes bland and lacks interest, then it is not fresh.
If you are looking to buy coffee beans online, Peet's delivers fresh coffee that is roasted to order. Try Peet's Coffee & Tea. Deep-roasted, delivered fresh, since 1966.
DOs and DON'Ts for Buying Fresh Beans
DO ask your retailer when the beans were roasted. If the retailer is selling from open bags or coffee bean storage bins, then don't accept any more than one or two days since roasting. If the retailer is selling beans in nitrogen injection packaging, then you can allow up to a week. Coffee has a generally accepted resting-period of 1-3 days after roasting. Ideally, it should spend this resting period in a nitrogen-flushed bag, as described above.
DO buy whole beans and grind them yourself at home.
DO beware of estate beans - these may have been sitting in the shop for quite some time due to their high price. Double check the date of roasting with the merchant.
DO buy smaller amounts of coffee more frequently. Buy as much as you would use in a week, on a weekly basis.
DO buy from a reputable retailer.
DON'T buy coffee in vacuum sealed bricks. In order to package coffee in brick-form, the coffee beans must be fully degassed before packing. This means the beans are already 'old' before they are packed.
DOs and DON'Ts for Coffee Bean Storage
DO store your beans in an air-tight, light-proof container. If you have a vacuum container, then use that. Otherwise, store the beans in the original vacuum bag.
DON'T store your beans in the refrigerator or freezer. Although the cooler temperature will slow the deterioration of the bean, it will not stop it. You are likely to notice the beans will absorb the smell of foods in the refrigerator. In addition, condensation forms on the beans each time you remove them from the cold.
Related reading …
Click for more about acidity, body, aroma and flavor.
Click for more about coffee blends and single origin coffee.
Click for more about coffee beans by region.
If you want to buy coffee online, Peet's Coffee and Tea has a section that allows you to select coffee by region before ordering. Peet's delivers fresh coffee that is roasted to order. Try Peet's Coffee & Tea. Deep-roasted, delivered fresh, since 1966.
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