1. First things first: what is the wet-hulled method?
Wet-hulled is the traditional processing method developed in Indonesian for commodity-grade coffee and results in this quality’s unique flavour profile: full-bodied, low in acidity, herbal and spicy with notes of chocolate and butterscotch. Despite its reputation, it is possible to find good wet-hulled coffee scoring above 80 points on the SCA scale.
Unlike fully washed coffee, which is hulled when the parchment reaches 11-12% moisture content, wet-hulled beans have the parchment removed at 30%-50% moisture content. The hulling might not happen for days, leaving the beans to ferment inside the parchment. They will then finish drying on patios.
This processing method is used because it’s fast. According to Troy, it gives farmers a product to sell one month after picking. This speed is desirable not only because of money but due to the archipelago’s unstable weather conditions, prone to heavy storms and high levels of humidity.
Finally, wet-hulled coffee requires a special hulling machine, the most common being the Dutch-designed Kemajuan. It needs a lot of friction to remove the parchment from the seed, which is swollen. The excess pressure can crush the beans, resulting in a higher than average percentage of defects if not done carefully.