La Cruz de Tarrazú Mill (Tarrazú) - Costa Rica

The Zamora Picado family has been in the coffee business since 1970, but it wasn’t until recently that the two brothers, Esteban and Felipe – who are now in charge of the family mill – decided to open a micro-mill to process special coffees from the Tarrazú region. They named their mill “La Cruz de Tarrazú” (Tarrazú’s cross) because of the area it is located in (a sort of crossroads within Costa Rica’s prime coffee growing region). The family are, above all, dedicated to the most stringent processing practices and are detail oriented and quality focused.

This Caturra & Catuaí lot was not only processed at the La Cruz de Tarrazú micromill but also grown entirely on farms owned by the Zamora Picado family.  The farms are maintained with the same attention to detail with which t he family manages its mill. Contributing farms are: El Olivo, El Pino, El Pozo, El Alto y El Anono – each are named accordig to a feature of the landscape or their location (for instance, ‘El Pozo’ means ‘The Pond’ and ‘El Pino’ means ‘The Pine’.

Currently all production on the farms is Caturra and Catuaí; however, the farms above are currently also being renovated with seedlings of several new varieties, including a natural mutation of Typica called ‘Villalobos’ and also the ‘Villa Sarchi’ variety.  El Pozo is the most productive and produces up to 1,200kg per harvest. Currently this farm is being renovated completely with Villa Sarchi.

Processing Selection processes are central to maintaining quality at the mill.  Coffee processed at La Cruz de Tarrazú goes through up to seven steps of classification depending on processing method.

First Stage: Selective Harvesting

Only the most ripe and mature cherries are picked during the harvest season. Seasonal workers are trained in selective picking and are very careful to only select the best cherries to deliver to the mill. Coffee cherries are again sorted when they reach the mill to ensure no damaged or underripes get through.

Second Stage: The ‘de-sander’

After being hand-sorted, the cherries are introduced into a type of flotation/separation tank. In the tank, all rocks, impurities and anything that could damage the pulping equipment is removed via a current of water that passes through a simple but effective mechanism that is known locally as a ‘desarenador’ (de-sander).

Third Stage: Flotation tanks

At this stage coffee is then washed through channels where underweight cherries, half empty cherries, dry cherries and other impurities of lower density are removed. Cherries are floated and all light density material floats to the top to be siphoned off. The heavier, denser cherries sink to the bottom and are then delivered to the pulpers. At this stage, some 10 to 15% of initially received volume is separated off.

Fourth Stage: Density & Size Sorting by Pulper

The mill uses a Pentagos DCV 183 pulper that is not only efficient but also allows for a great deal of density and size sorting. After being floated, ripe and heavy cherries are delivered to the pulper. Before they are pupled, the cherries pass through an elastomeric material that is able to separate out harder and more immature seeds and prevent them from being pulped. The seeds of those cherries that are pulped pass through a seive where they are separated according to size.

After pulping, coffee is processed using either the fully washed, the double washed or the honey method. This lot has been processed using the honey method. Coffees processed at the mill using this method are moved immediately to the mill’s extensive African beds to pre-dry in the sun for 2 to 3 days, until the surface humidity has stabilised.

The coffee is then moved to African beds within the mill’s greenhouses, where it will continue drying slowly at around 36˚C. Coffee is turned regularly and moved from the lower to the top beds as it dries. Once it reaches 10.5% humidity, it is stored and rested to prepare for dry milling and export.

In addition to removing the parchment layers, the coffee goes through yet additional rounds of selection during the dry milling process.

Fifth Stage: Grading by Size

After the parchment layer is removed, the coffee is moved through the Size Grader where it passes over layered screens, each with different sized perforations. The largest is on top and the smallest on the bottom. At each level, the beans are ‘graded’ to a particular screen size.

Sixth Stage: Grading by Density

After being graded by size, the green coffee is then channeled through a density grader to determine the integrity of the different beans. The density grader features a metal plate positioned at a slope. The plate is vibrated with less dense beanse gravitating down the slope. The dense beans will gravitate up the slope. The different densities are channeled into different chutes and kept separate.

Seventh Stage: Handsorting

Classification activities conclude in handsorting. The mill has multiple lines for handsorting and at each line there are at least 6 people stationed. Coffee is introduced down the line on a conveyer. The stationed workers visually asssess the coffee and remove any broken, damages or discoloured beans as they are moved down the conveyor.  This is one of the best ways to ensure a zero defect coffee, though it is highly labour intensive.

In addition to honey processing, the mill also produces Fully washed coffee, Double washed coffee and Natural lots. For all proceses, drying is completed entirely using African beds.

Another important advantage is that the farm is able save great amounts of water by using the honey and the natural processes. Using the honey method saves more than 3 gallons of water per pound of coffee. Natural processed coffee doesn’t need any water at all.

About Honey Processing:

‘Honey’ processing is a form of semi-washed process that is common across Costa Rica. Different designations of white, yellow, red and black honey are commonly used among Central and South American farmers and commonly refer to differences in:

• the amount of mucilage left on the bean after pulping;
• how the beans are dried (i.e. direct sunlight or shaded conditions);
• the length of time and conditions under which the beans are dried.