Gayo is an arabica coffee named after its origin, Gayo highland that located in Aceh, Sumatra, Indonesia. Gayo coffee comes from the variety of Ateng and S-Lini. This coffee is planted in the altitude higher than 1.400 meters above sea level, making this coffee delivers a distinct and unique coffee quality. Same as mandheling, gayo has a full body coffee with relatively low acidity. The character of gayo coffee is majored by floral notes such as black tea or dried fruit, but it still have Sumatran arabica spice notes like ginger, clove, and lemongrass with butterscotch and dark chocolate finish.
The first step of coffee processing is harvesting. Around 3 to 4 years after plantation, coffee trees will bear fruit called cherry coffee or cherry. When it is ripe, the cherry will have a bright deep red colour. The harvesting process could by stripping all of the cherries in one time with hands or machine or only harvested the ripe cherries by picking it individually with hands. To prevent spoilage, once cherry coffee has been picked the processing needs to be done as soon as possible.
Processing coffee cherries
Coffee manufacturing process are vary, based on what kind of product that wants to be achieved. For Gayo coffee, the processing is semi-wash.
Wet hulled (Washed/Semi-wash)
Wet hulled process consists of full wash or washed and semi-wash. The difference between these two methods is in the volume of the water that is used. Semi-wash process only used half of the full wash process water.
The cherries are passed through a pulping machine or pulper to separate the skin and pulp from the bean. Then the beans went into the screening process by separating them by weight in water channels. The lighter beans will float on the top, while the heavier ripe beans will sink to the bottom. Then, they are separated by size using a series of rotating drums. After screening, beans then fermented inside water-filled fermentation tanks for 12 to 48 hours to remove the slick layer of mucilage. If the mucilage is separated, beans then rinsed and prepared to be storage by drying them until the moisture content is 11%
When the moisture content of beans reaches 11%, the beans are passed through huller to remove the parchment layer (endocarp) for the wet and honey processed beans, and removes the entire dusk husk of the dried cherries for the dry processed beans.
Grading and sorting
Before packed, beans are graded by size and weight. Beans are sized through a series of screens by sorted the heavy and light beans using air jet. After that beans are sorted by reviewing for color flaws or other imperfections by manually using hands or by machinery.
Packaging the green coffee
After milled, beans now referred to as green coffee or green beans. The beans then packaged in either jute or sisal bags to be shipped or storaged.
Gayo coffee could be used as single origin coffee or blend coffee.
Based on the SCAA (Specialty Coffee Association of America) the grading for coffee are:
Test Weight : 300 gr
Moisture Content : 9% − 13%
Total Defects : 8
Primary Defects : permitted (from 9 to 23)
Size : 50% greater-than or equal to 6 mm;
5% less than or equal to 5.5 mm
Quakes/Unripe Beans : 5
Cup Faults : -
Gayo coffee is categorized as arabica coffee.