Choosing Coffee Beans
How should one go about choosing coffee beans? Well, tastes differ and this makes it a slightly tricky question to answer, however, as it is often the case, whatever the taste, there are always some basic principles to observe if you are on a quest to find the most delicious coffee.
Your Coffee Must Be Fresh
First and foremost, your coffee must be fresh. If stored properly (see my previous post), roasted coffee beans are at their best for about a month after roasting. Again, if stored properly, the life of roasted coffee can be extended somewhat, but fading of taste and aroma will be increasingly noticeable with every new day. Any respectful speciality roaster puts the roasting date on the bag, if the roasting date cannot be found on the bag - this is usually not a good sign and suggests the roaster prioritises operational efficiencies (afforded by long sell by dates) above the quality of your coffee.
Ground coffee loses its freshness incredibly fast. Coarsely ground coffee (say ground for cafetiere) will lose most of its freshness in about three days. Fine ground coffee (e.g. ground for espresso) will lose half of its freshness in about 15 minutes! Whatever brewing method you choose, we recommend grinding coffee immediately before brewing. Even using the cheapest of blade grinders is immensely better than using ground coffee, however, if you are serious about your coffee, we recommend getting a burr grinder (my earlier post, how to brew the perfect cup of coffee, includes some inexpensive burr grinder recommendations). Burr grinders are designed to grinds coffee into particles that are significantly more uniform in shape and size than those achieved with a blade grinder – this in turn allows uniform extraction of coffee preventing excessive bitterness and allowing consistent control of brewing times.
Coffee is an agricultural product and as such its freshness is not limited by how recent the roasting date is. The green coffee used by the roaster should be seasonally fresh. Once harvested and processed, depending on the quality of processing and the method of storage green coffee is at its best for a period of up to nine months. It is the responsibility of the roaster to ensure that the coffee they roast is fresh. Very unfortunately some roasters often use green coffees that are well past their seasonal glory, usually hiding the unpleasant signs of green coffee age behind the darkness of its roast. It is much harder to hide the age of coffee in a lighter roast, so, generally, if you like your coffee and it is roasted in the light to medium-dark range, the chances are it is seasonally fresh.
Pay Attention to Varietals, Origin and Processing
There are dozens of varietals of Arabica coffee and, complemented by environmental and climatic factors, they all have different taste. In addition to varietals and environmental factors, the processing of coffee has a major impact on its taste. Washed coffees tend to have very clean taste, whilst natural processed coffees are often more earthy, sometimes gamey, sometimes overtly fruity or slightly (and sometimes not so slightly) fermented. Nothing beats tasting when choosing a coffee, but once you have paid attention to the cultivars, origin, altitudes and processing, you will find it immensely easier to select coffees that you really like.
Coffee Strength
Finally, what about your coffee strength? To be honest, "coffee strength" is as misleading a term as a sell by date. Coffee strength refers to the degree of roast, i.e. "stronger" coffee is a darker coffee. However, the darkness of coffee has nothing to do with how strong (in terms of coffee flavours or caffeine extraction) your beverage is. It is simply a reference to body resultant from the progressively increasing (with a degree of roast) presence of roasty flavours. Generally, a darker roast hides the subtleties present in the lighter roasts and this is precisely why the majority of most delicate and exquisite coffees are roasted light. This is not to say that a dark roast is necessarily bad; some coffees take a darker roast well, preserving their acidity and taking on a very interesting character, but most coffees, unless they have too many defects or show signs of age that need to be hidden, do better as a lighter roast.
Darker coffee does not contain more caffeine. The process of roasting does not add or remove caffeine from the coffee beans. True, as coffee is being roasted darker, everything else being equal, it loses more of its moisture content and by weight darker coffee will have slightly more caffeine, but this effect is marginal and generally it is negated by a plethora of other variables such as varietals, elevation (higher grown coffees are denser and lose less weight through roasting than lower grown ones) and so on.
Extraction of coffee, expressed as percentage of the final brew, is probably the only way to measure correctly how strong your coffee is. However, coffee, unlike tea, has a very narrow sweet spot – it does not taste great if it is under or over-extracted. This is precisely why most of the speciality coffee associations, and there are quite a few of them on both sides of the Atlantic, including SCAA (Speciality Coffee Association of America based in the US) and SCAE (Speciality Coffee Association of Europe based in the UK), recommend almost identical extraction ratios for brewed coffee. It really does not matter how light or dark your coffee is, to get the best taste of your coffee you need to consistently extract about 20% of coffee to achieve about 1.35% concentration of coffee in your ready brew. Needless to say, this is easier said than done and this is why coffee brewing is often considered to be nearly as much of a science as coffee roasting.
Don't forget - Coffee Tasting with The Beanberry Coffee Company - at Tastes Delicatessen, 92 High Street, Eton - on Sunday 9th December - between 11am and 3pm.
