Flavor Exploration | Flavor Differences of Washed Yirgacheffe Woka Under Different Roasting Methods?

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Exploring Woka Coffee: Roasting Experiments

In our daily routine, we dedicate time to adjusting roasting curves to explore how to make the same coffee bean taste better. Today, we'll use Woka coffee for our experiment.

Woka Coffee Origin

Woka is located in the Yirgacheffe region, at an altitude of 1800-2000 meters, using a garden coffee system. It belongs to the Sidamo region but was separated due to its unique flavor profile. Besides the town of Yirgacheffe, it includes three surrounding sub-regions: Wenago, Kochere, Gelena, and Abaya. Under Yirgacheffe, there are numerous villages, micro-regions, cooperatives, and processing stations. In most parts of Ethiopia, coffee farmers still face difficult living conditions. They don't have sufficient capacity to build family-style processing workshops, which is why many processing stations emerge - they centrally purchase coffee cherries from surrounding small farmers, process them, and then sell them to green bean suppliers.

Woka Cooperative

The Woka Cooperative was established in 2005 and joined the famous Yirgacheffe Coffee Farmers Cooperative Union (YCFCU) in the same year, becoming well-known for producing high-quality natural processed Yirgacheffe coffee. The Woka Cooperative has approximately 300 coffee farmers.

Processing Method

Using refined washed processing, the coffee is placed in washing tanks for about 72 hours for fermentation to remove the parchment. Some of the acid produced during the mucilage fermentation process enters the beans. At the same time, since there's no pulp and mucilage attached to the parchment during drying, it lacks the characteristic fruity aroma of natural processed coffee, with flavors leaning toward clean and bright, and more noticeable acidity. It's then placed on raised beds for drying, manually selected, and after passing quality inspection by the Ethiopian Coffee and Tea Authority, it's traded and exported through competitive bidding. The coffee flavor possesses pure and refreshing characteristics.

Roasting Comparison

FrontStreet Coffee's roaster has roasted two different roasting curves for Woka - one is the standard production curve, and the second is a special roasting curve. Let's compare which roasting method produces better-tasting beans. We'll use the same pour-over parameters for comparison:

FrontStreet Coffee Pour-over Parameters

90°C water temperature, BG 5R grind (64% pass-through rate on China standard #20 sieve), 16g coffee grounds, 1:15 coffee-to-water ratio.

FrontStreet Coffee's Barista Brewing Recommendation

25g water for 30-second bloom, first pour with small water flow to 127g, second pour with slightly larger water flow to 227g.

Tasting Results

Standard Roasted Woka

The acidity is more obvious and delicate, presenting yellow lemon acidity, light cane sugar sweetness, sweet and sour balance, cream and lemon tea flavors, with green tea and floral aftertaste. The mouthfeel is smooth, the flavor is full-bodied, and the aftertaste is relatively long-lasting.

Special Roasted Woka

Citrus acidity is obvious, with apple acidity and berry flavors. The sweet sensation is distinct, with pomelo peel notes. There's astringency in the middle section, and although there's a tea sensation in the finish, the aftertaste is insufficient, with flavors dissipating relatively quickly.

FrontStreet Coffee Roaster Analysis

The standard roasted Woka has a relatively gentle temperature rise, with a roasting time of just over 10 minutes. This provides sufficient time and temperature for dehydration, allowing chlorogenic acid to degrade. If degradation is insufficient, the coffee will taste sharp with uncomfortable acidity and a rough mouthfeel. At the same time, continuing to apply heat after the first crack allows the caramelization reaction to continue, producing caramel and other sweet flavors. The sweetness is more solid and weighty, while the bright fruit acidity decreases slightly.

The special roasted Woka has a rapid temperature rise before the first crack, reaching higher temperatures, belonging to a relatively fast roasting rhythm. The heat is maintained constantly, then suddenly reduced to 0 one minute before the first crack, using residual heat to let the beans slowly transition into the first crack. After the first crack begins, heat is restored to accelerate the development of the first crack, with a development time of 2:00 before removal at 191.1°C. This belongs to a fast-roasting technique. Why operate this way? Low-temperature roasting can preserve more volatile floral aromas and bright fruit acidity, while adding heat after the first crack compensates for the insufficient heat in the early stages, allowing the coffee bean surface to expand and making the flavors more mature.

So, when brewing the special roasted Woka, the sweet sensation is very prominent, carrying bright bergamot, citrus, and pomelo peel acidity. However, the downside is that although there's explosive fruit acidity, the acidity retention time is short, and the finish is insufficient. The standard roasted Woka maintains a lasting green tea sensation with a more balanced mouthfeel.

Conclusion

Does this mean fast-roasting techniques are inherently bad? This is subjective. When expressing the characteristics of beans, appropriate adjustments to balance flavor and mouthfeel are what make coffee truly enjoyable.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473