Coffee Corner 102: Spilling the Beans
In this series, we talk about, we share some thoughts about what you'll need to set up your own coffee corner for espresso and what it'll all cost. Of course, we're going to be talking a lot about our espresso machine packages and why we think they're a great value.
In this second instalment of Coffee Corner 101, we'll be talking about coffee beans and how to store them.
Fresh beans make good coffee. Whereas filter / pour over coffees can handle newly roasted beans well, for espresso-making the sweet spot for beans is generally 1 to 4 (maaaybe up to 6) weeks after roast.
Once beans are roasted, they begin to release gases (mainly carbon dioxide) in a process known as degassing. There isn't much room in the espresso extraction process to allow degassing so much of the carbon dioxide ends up in the shot. Allowing the beans to rest and degas for about a week after roasting will yield a more balanced espresso with less spikes in acidity or bitterness.
On the other hand, we can't leave beans too long! Oxygen in the air will cause the beans to oxidise, and beyond a certain point the beans begin to taste stale and unpleasant. This generally happens around 4 weeks after roast, although we've had good coffee from beans as old as 6 weeks.
Practical tip - When you're buying coffee, check the roast date and not the best before or expiry date. Supermarket coffees can be shockingly old (2, even 3 years), and we avoid them like the plague (we atas that way). Get your beans from your neighbourhood café or from a local roastery (there are a few online too) to get the freshest beans and #supportlocal. When we're not experimenting, the TLG team get our regular beans from a secret micro-roastery in a friend's backyard.
Arabica, Robusta or Others
Most espresso beans are pure Arabica, which are understood to be more flavourful and carry tasting notes generally thought to be pleasant (chocolate, sugar, fruit, berries). Some coffee roasters include Robusta in their blends - usually to produce better crema, increase caffeine content, or simply to lower cost.
Kopi at coffeeshops are usually Robusta, but mixed with other fillers during the roasting process (corn, chickpeas and chicory). You generally won't find pure Robusta espressos in Singapore, but from what we read online they're generally thought to be unpleasant. However, as we always say, it all comes down to personal taste.
(TLG Eugene: I've tried 100% Robusta and it wasn't half bad, just very flat-tasting with notes of cardboard, leather and something musty, akin to sweaty armpit. Not joking.)
There are other coffee varietals as well - Liberica is grown in neighbouring Malaysia, Indonesia and the Philippines. We haven't had the fortune of trying them yet, but at the time of writing we've got a bag on the way from a local roaster. Will share more at some point.
- Buy and store beans always - they stay fresh longer because there's less surface area for oxidation, and the grinding process releases fresh oils and gases that help make good-tasting espresso.
- Try not to leave beans in the bags they come in - while those bags are great for retailing beans in and have one-way valve, they're notoriously unreliable especially when you're opening and re-sealing them over and over again. All it takes is for your beans to be exposed for a day, and you'll find a precipitous drop in quality.
- We think it's a good idea to buy containers specially designed for coffee storage. These have a one-way valve allowing excess gases to escape (helping with degassing) but not enter (slowing down oxidation). We recommend our stainless steel coffee containers which even include a nifty date indicator so you won't forget when your beans were roasted! [Link]
- Cafés / local roasteries generally retail 250 g packs of beans for between S$12 and S$25. Any more than that, the beans are likely to be single origin or unique in some other way.
- Get one of our coffee storage containers, which cost between S$16 and S$20. Small investment to save yourself from wasting a bag of coffee beans that costs around the same amount.
That was a long post! In Coffee Corner 103 we'll be talking about what we do to prepare the ground coffee for brewing, and ideal temperature and pressure for brewing that delicious espresso.