Where Do the Floral and Fruity Aromas of Coffee Beans Come From - Is It Determined by Roasting? How to Brew Coffee for Sweetness

Understanding Coffee Through Packaging Information

When a bag of specialty coffee arrives, the label always carries a set of information: origin, estate, altitude, variety, roast level, and flavor notes, among others. Each detail is an important factor for judging the quality and flavor profile of the beans.

Coffee flavor is built up gradually through the terroir that nurtures the plant and the processing method applied afterward. So how can we read coffee flavor accurately from that information?

Why, for instance, can a bean from Ethiopia display such rich fruity aromas?

Flavor Determined by Terroir and Cultivation System

Altitude

The altitude of a growing region is considered a crucial factor affecting bean quality. The Ethiopia Buku Abel featured here sits at a high altitude of 2,250-2,350 meters.

Compared with lower-altitude areas, high-altitude regions have cooler temperatures and a marked swing between day and night. Much as the temperature difference makes Hami melons so sweet, this swing slows the coffee's growth and leaves the cherries with a higher content of aromatic precursors such as sucrose, organic acids, trigonelline, and fruit esters.

As a result, high-altitude beans are denser and richer in organic matter. In the cup they show pronounced acidity with pleasant fruit notes like grapefruit, citrus, and berries.

Low-altitude beans, by contrast, are less dense and more balanced but relatively plain.

For specialty beans, even though some fine coffees still come from low altitudes, high altitude has become a widely recognized marker of quality.

Thanks to that altitude advantage, the FrontStreet Coffee Ethiopia Buku Abel featured here presents rich fruity aromas: passion fruit, guava, strawberry jam, berry sweetness and acidity, and apricot.

Cultivation Systems

The best growing regions for coffee sit in mountainous countries between the Tropics of Cancer and Capricorn.

Within those regions, different cultivation systems directly shape flavor. Take Ethiopia, where coffee growing can be divided into forest coffee, semi-forest coffee, garden coffee, and plantation coffee.

Forest and semi-forest coffee are nearly wild: coffee trees grow scattered through the forest, and during the red-fruit season farmers enter the woods, under government protection, to harvest them. Or they come in regularly to prune and carry out simple maintenance.

In this near-primitive state, the trees are of mixed varieties, which naturally yields more diverse flavors.

That is why, tasting the FrontStreet Coffee Ethiopia Buku Abel, you can find rich spice notes such as cinnamon amid the bright fruit aromas.

Coffee Varieties

Variety is an important factor in taste. But like any plant, coffee has countless varieties, and they are hard to keep straight.

You should still know about the veteran Typica variety, which carries excellent aroma and a mild acidity. Indonesian Mandheling, Jamaican Blue Mountain, and Yunnan Xiaoli are all derived from Typica.

There is also the veteran Bourbon variety, with its rich body, strong aroma, and very bright sweetness.

The FrontStreet Coffee Ethiopia Buku Abel featured here is of the group known as Heirloom.

Strictly speaking, Heirloom is not a single variety. Ethiopia holds so many coffee varieties, like a natural gene bank of Arabica, with types too numerous to classify.

To protect local coffee, the government is unwilling to disclose specific variety information, so the native types are grouped together under the name Heirloom.

Processing Methods

The FrontStreet Coffee Ethiopia Buku Abel featured here uses the natural process. The most common processing methods fall into three broad categories: natural, washed, and honey. Natural processing is the oldest technique of all.

Traditionally, Ethiopia has used the water-free natural method since ancient times, relying on sunlight and heat to remove moisture naturally. When it comes time to sell, the dried fruit is crushed and taken to market.

Naturally processed beans carry several advantages: they retain more of the beans' fats, acids, sugars, and other organic compounds, presenting a richer and more intense aroma.

Yet natural processing leaves many uncontrollable factors. With too many defective beans, all manner of indescribable wild flavors can appear: bleach, fermented tofu, onion, or even durian and worse.

The bean hunter behind this lot, Mr. Li Lin, has used modern technique and meticulous processing to overcome the pitfalls of the natural method.

So the FrontStreet Coffee Ethiopia Buku Abel featured here, while banishing the strange wild flavors, fully highlights the advantages of natural processing: the intense fruit of the origin shows even more exotic passion fruit character under the natural method.

And that exotic fruit quality is unique to naturally processed beans.

Roasting Technique

Chen Hao, the roaster for the coffee subscription program behind this lot, understands deeply that coffee flavor is formed through the interplay of many factors.

The same variety, grown in different regions, will present different flavors.

Take the same Caturra variety: grown at the Canet Estate in Tarrazú, Costa Rica, and processed with the raisin honey method, it shows fermented grapes, passion fruit, strawberry, black tea, and toffee.

But in the Pital region of Huila, Colombia, after washed processing, its profile becomes cocoa, hazelnut, caramel, and almond.

So bringing a bean to the cup accurately and completely, while restoring its origin character as fully as possible, is his passion.

Coffee science books tell us that roasting is mainly divided into light, medium, and dark, and that roast level can be controlled through the phenomena of "first crack" and "second crack."

To Chen Hao, though, those are only surface signs. The essence of roasting lies in the Maillard reaction, and specifically in the important moment when caramelization begins within it.

The Maillard reaction is a complex chemical reaction common in cooking, and it is what makes coffee aromatic.

Chen Hao believes that extending the reaction time during roasting increases flavor complexity, while raising heat and shortening the reaction time reduces complexity but increases intensity.

Coffee's floral and fruity aromas are the product of the most intense Maillard activity at 150-170°C.

Nut, caramel, and chocolate aromas are products of temperatures above 170°C.

The FrontStreet Coffee Ethiopia Buku Abel featured here belongs to the floral and fruity acid category, and should follow that roasting curve.

He holds that extending the 150-170°C reaction time increases the diversity and complexity of flavors during the Maillard stage, then raising the heat after 170°C delivers strong sweetness with a hint of nuttiness.

Working from these principles, Chen Hao tests and cups repeatedly during the roast until he finds the perfect curve and flavor. And what is that perfect curve?

To Chen Hao, the most perfect curve should restore the origin character as fully as possible, letting baristas and drinkers clearly perceive the bean's personality.

And the FrontStreet Coffee Ethiopia Buku Abel featured here was born through just such a process.

Belonging to FrontStreet Coffee's Ethiopia Goro Estate Buku Abel, under the roaster's hands it becomes a full cup of bright, clear tropical fruit: passion fruit, guava, strawberry jam, berry sweetness and acidity, and apricot. And the rustic charm of the Hambela girls lingers as a faint spice aroma.

FrontStreet Coffee Recommendation

To explore this natural, fruit-forward side of Ethiopia, FrontStreet Coffee's Sun-Dried Huakui is a strong choice. It comes from the Hambela region of Guji, Sidama, where a 200-hectare farm follows a traditional natural process. To keep the cherries from molding or taking on off-flavors, workers spread the ripe fruit on raised beds to dry for 21 days, turning it constantly for an even dry and hand-sorting out any defective or moldy beans every three to five days. Once the skin has dried hard it is hulled off, and the green beans are sorted a final time.

Because the fruit dries on the bean, a light to medium roast draws out a light fermented wine aroma along with floral, citrus, and mango notes. The cup is rich and complex, with honeyed sweetness, a cocoa accent, and a touch of spice, a thick body, and a long finish. It makes an ideal companion to the naturally processed Buku Abel described above, and rewards a patient pour-over that lets the layered fruit unfold.