Purchasing and Storing Coffee Beans

Purchasing and Storing Coffee Beans

Freshness is the life of coffee. So how do you tell whether the beans in front of you are fresh?

There are three steps: smell, look, and snap.

Smell

Hold the beans to your nose and breathe in deeply. If the aroma of the coffee comes through clearly, they are fresh enough. If it is faint, or has already begun to turn rancid in the way peanuts and other nuts do when they are left too long, the beans are past their best.

No amount of care at the grinder or the brewer will rescue coffee like that. A good cup simply cannot be made from it.

Look

Tip the beans into your hand and spread them out. Look at the origin and the variety, and check whether the roast is even across the batch.

Snap

Take one bean and try to split it with your hands. A fresh bean gives way easily, with a crisp sound and a clean break. A stale bean makes you work for it, even for a single bean.

Splitting a bean tells you something else as well: whether the roast was even. If it was, the outer surface and the inner core should be the same color.

If the surface is noticeably darker than the inside, the roast heat was probably too high, and that too will have cost the beans aroma and flavor.

What to Look for When Buying Coffee Beans

Start by choosing a shop that is thriving and turning its stock over. Freshness is the life of roasted coffee, so look for a shop that keeps its beans cleanly stored, away from oily residue, out of direct sunlight, and clear of anything hot. A roaster that sells its own beans and takes pride in their aroma is usually a safe bet.

When you buy roasted beans, you can ask for a clean, bright-tasting lot. If you lean toward a little acidity, say so; if you prefer pronounced bitterness, say that instead. Or simply tell the staff what you enjoy and let them choose for you.

If you have the shop grind the beans for you, tell them exactly which brewer you will be using, so they can set the grind to suit it: an electric filter machine, a filter cone, paper, a siphon, and so on.

When you buy canned ground coffee in a supermarket, pick a product with clear labeling, such as the bean type or the flavor profile it aims for, and match it to your own preferences.

How to Store Coffee Beans

Roasted coffee is highly susceptible to the oxygen in the air around it, which oxidizes the oils inside the bean. The aroma volatilizes and disappears, and heat, humidity and sunlight all accelerate the decline.

Decaffeinated beans, which have already been through several processing steps, oxidize even faster. Keeping the aroma and quality of coffee intact therefore makes packaging and storage a serious discipline.

After roasting, coffee releases carbon dioxide in a volume roughly three times its own. A good package therefore has to do two jobs: keep oxygen out, and deal with the carbon dioxide the beans are still giving off.

Airtight Packaging

The most common approach: beans or ground coffee sealed in a tin, a glass jar, a paper bag or a plastic container, then closed with a lid or a seal. Protection is poor, and because the coffee sits in constant contact with air, it needs to be finished quickly, within about one week.

Vacuum Packaging

Here the container is filled with coffee and then had the air drawn out of it. Even so, "vacuum" is an overstatement: at best it removes ninety percent of the air. And because ground coffee exposes far more surface area than whole beans, even the small amount that remains is enough to react with it and dull the flavor.

Gas-Flush Packaging

This uses a metal bag fitted with a pinhole. Once the coffee is inside, inert nitrogen is injected, driving the carbon dioxide out through the pinhole. It is a widely used method, but once the flushing gas is gone, oxygen slips quietly back in through the same pinhole.

Oxygen-Absorber Packaging

A sachet of deoxidizing and decarbonizing agent is placed in the bag. It readily absorbs the air inside the pack, and the carbon dioxide the coffee gives off as well. Its drawback is that it absorbs some of the coffee's aroma along with them.

UCC Aroma Packaging

At present this is the most effective system of all, and it is always used for whole beans rather than ground coffee. It resembles a pinhole metal bag, with one crucial difference: gas inside the bag can escape through the pinhole, while a one-way valve stops oxygen outside the bag from getting in.

Roasters cool and pack the beans immediately after roasting and inject nitrogen to expel the air inside. It is close to ideal, but the materials are expensive and the costs are high, so today only a handful of large companies use it for selected coffees.

FrontStreet Coffee: http://www.gafei.com

FrontStreet Coffee Recommendation: Beans Worth Storing Well

Buying well is only half the battle; the beans also have to suit the way you store and brew them. FrontStreet Brazil Queen Estate is a reliable everyday choice: a yellow Bourbon from Brazil, the world's largest coffee producer, medium roasted to bring out cream, peanut, chocolate, toast and sugarcane sweetness. It performs as well in a pour-over as it does in a moka pot or an espresso machine, so one bag covers every brewer in the house. If you prefer a classic, balanced cup, FrontStreet Jamaica Blue Mountain No. 1, a Typica grown in Jamaica and medium roasted, layers chocolate, roasted nuts, cream and caramel without a sharp edge. Buy fresh, decant into small airtight jars, and both will taste the way they did on roast day.