BeanScene Magazine

The creation of a delicious coffee involves many contributions by many people along the way. In this instalment, I took a rare chance to explore the contributions not of the roasting of the coffee in Australia, but of the processing of the coffee at origin. I was able to do so thanks to a sample pack of three coffees from El Salvador’s Finca Manzano, processed in the washed (or wet process), natural (or dry process) and pulped natural styles.

Processing

The various coffee processing methods all result in the separation of the seed of the coffee cherry from the remainder of the fruit. The wet process is the processing method that we are most familiar with for Central American coffees. It begins with the mechanical pulping of coffee. The resultant mixture of pulp, coffee beans and water is fermented to allow for the pulp to be separated by washing, after which the green coffee bean is dried, rested, and the parchment layer surrounding it removed at the dry mill. The use of water also allows the separation of defective beans by flotation.

In contrast, the dry process technique achieves the separation of fruit from seed by drying the fruit on patios and then mechanically removing the dried fruit. The natural process technique allows fewer opportunities to sort out defects and can also allow for the development of unique defects, such as mould on the fruit if it is not turned correctly as it dries.

The pulped natural method is a hybrid between the two, in which much of the coffee pulp is mechanically removed, as in the wet process method, following which the remaining fruit and pulp is dried, rather than fermented.

Roasting

For consistency, I roasted each coffee to roughly the same profile: a darker roast filter coffee. For the roasters out there, my roast profile was as follows: the minimum bean temperature of 100 Celsius was reached after loading coffee, following which the maximum temperature of 210 Celsuis was reached in 11.5 to 12 minutes, with a four minute cooling to room temperature thereafter. Airflow was increased at the 5 and 10 minute marks. This yielded coffee with a mass loss of 15 per cent from the green coffee.

Of course, this roast profile is specific to my equipment and desired outcomes, but please do let me know if you experiment with it. Ordinarily, I would prefer a slightly shorter roast to a cooler temperature for filter coffee, but I chose this profile to try to emulate the suggested roast for the World Cup Tasting Championship. To keep me honest in my blind tasting, I also roasted a batch of Brazil Carmo Estate to the same profile as a reference sample.

In the cup

The Brazil Carmo Estate was easily recogniseable by the strong roast peanut flavour. The wet processed coffee was my favourite, presenting a well-rounded, clean and complex flavour profile, with a pleasant citric acidity retained, despite the darker roast, and floral hints, backed by a medium-high sweetness.

The pulped natural and natural processed coffees suffered from earthiness or mustiness, perhaps accentuated by the roast level. To my surprise, the coffee with hints of pineapple turned out to be the pulped natural, whilst the natural processed coffee that I presumed would be most likely to display such flavours was distinctly flat and low in sweetness.

Conventional wisdom held true in that the natural processed coffee had the highest body, yet the wet processed coffee was no slouch, rating a medium-high in this category.  See the tables for more details.

Luca Costanzo runs www.coffeereviewaustralia.com. The El Salvadorean sample lots were purchased from Sweet Marias. The Carmo Estate samples were donated by Melbourne Coffee Merchants.