Probably like many of you, when we first became involved in the coffee business, we drank coffee every day, yet knew very little about how the magical stuff that helps us begin the day every morning got from a tree on a far-away tropical farm into our mugs.
Here's some of the story that we've learned so far!
And here's more About Bolivian Coffee specifically.
Coffee Production & Processing
Coffee beans aren't actually beans, but are the seeds of a tropical tree. There are two primary types of coffee trees: Arabica, which grow best in high altitude, shady environments (under the shade of taller tropical trees), and Robusta trees, which are more bushy and grow better in lower-altitude, sunny environments. Arabica beans are harder to grow, have a better and more nuanced taste, cost more, and contain less caffeine than Robusta beans. Specialty coffees are all 100% Arabica beans, while instant coffee, commercial-grade coffees (i.e. Folgers, Maxwell House) as well as some higher-end espresso roasts, are blends of Robusta and Arabica beans. A little Arabica is mixed in to improve the harsh taste of Robusta beans, and add the sought-after “crema”, the frothy, white top of an espresso shot.
All Bolivian coffees are 100% Arabica coffees. Within the Arabica species, there are actually several different types of varietals (similar to different varietals of grapes used to make wine, such as Merlot, Chardonnay, or Cabernet grapes) of coffee trees, including Tipica, Bourbon, Catuai, Caturra, which are all common varietals grown in Bolivia.
A coffee tree produces small fruits called cherries (which look a lot like real cherries), which typically turn red as they become ripe, although there are also some varietals that turn yellow, like these:
Different cherries on the same tree branch will ripen on different days, so one of the most important factors determining high quality from low quality coffees are the care with which farmers pick the cherries. Ideally, all cherries are picked from the branch only when they are perfectly ripe. Unripe or overripe beans that are mixed in with the ripe beans will lower the quality of the taste of that batch of coffee.
In order to do this, all cherries must be hand-picked, by trained workers who know how to tell which cherries are ripe. Large-scale, industrial coffee plantations (such as those common in Brazil, the largest coffee producing country in the world) will use harvesting machines that shake the coffee branches and collect the cherries mechanically. Of course, this means that some un-ripe beans will be included, and the coffee will be of lower quality overall than painstakingly hand-picked batches of coffee cherries. All the Bolivian farmers that Invalsa works with hand-pick all of their coffee cherries, often employing some neighbors and part-time workers to help out during the busiest times of the coffee harvest.
After the cherries are picked, the next step is to remove the cherry pulp from the two beans inside each cherry. (Fun fact: in about 10% of cherries, the beans have not separated into two separate halves, and are still fused into one oblong bean. This is called a “peaberry”, and a special peaberry lot is always one of Invalsa’s annual micro-lots from Bolivia.) There are two methods of doing this: the wet method and the dry method. All Bolivian coffee uses the wet method, but the dry method is very common in Brazil, the largest coffee producing country, so we will summarize it below after describing the wet (or ‘wet washing’) process.
Wet processing involves running the coffee cherries through a de-pulping machine along with a lot of water, in order to remove and rinse the pulp (or ‘mucilage’) off of the coffee beans inside each cherry. There are large, mechanical machines that do this is more advanced coffee countries, but all of the Bolivian farmers that Invalsa works with do wet washing in small, hand-powered machines, such as the ones pictured below. To use this machine, cherries are poured into the funnel on top, then the crank on the side of the machine is turned by hand in order to move the cherries through the de-pulping machine. The pulp (or ‘cascara’ in Spanish) falls out onto the ground below, while coffee beans come out of the front of the machine and are caught in a container in front. The cascara is the composted for use as fertilizer, or drunk as a kind of coffee-tea, called “sultana” in Bolivia and other South American countries.
The beans then need to be fermented for 8 to 16 hours (to remove the last of the mucilage) before they are thoroughly washed again, in clean water, in order to remove the last bits of pulp attached to them. The next step is drying the beans until they reach a 12% humidity level, at which they can be bagged and stored without fear of mold or fermentation.
Large coffee processing plants may have mechanically powered drying machines to speed this process, and help prevent the risk of rain falling on drying beans. However, all of the farmers that Invalsa works with in Bolivia use sun-drying, by placing their coffee beans on large drying patios, such as those pictured below (these drying beds are at Celso Mayta's farm, Finca Golondrina, as are the washing machines pictured above.) Once the coffee is dry, the farmer bags it in 132-lb bags and can bring it to a local market to sell, or deliver it to a pre-arranged buyer. Before final bagging and export, the coffee goes through a final milling at a ‘dry mill’, where the papery parchment (‘pergamino’ in Spanish) that remains on the beans is removed.
Coffee is then packaged for distrubtion. Burlap bags that contain about 132 lbs. of coffee are the traditional packaging material, but they allow for contamination, and absorption of humidity and smells during transportation. More secure packaging options include vacuum-sealing in plastic or foil bags, a method that Invalsa uses for its highest-quality coffees, or using special plastic bags made by a company called GrainPro which are sealed with a zipper in order to make a hermetic seal that prevents any contamination of the coffee during transportation and storage. Invalsa bags all of its coffees (unless they are vacuum-packed) in GrainPro bags in order to preserve quality, and is also the licensed, exclusive distributor of GrainPro bags in Bolivia and Chile.
In the “dry process” (also called "natural process"), coffee cherries are left intact to dry in the sun, like raisins. Once dry, the dried pulp and parchment are removed from the beans inside using a dry milling machine (the same one used to remove parchment in the dry milling step in the wet washing process). This process has fewer steps and takes less time than the wet washing process, however, it creates an earthy, herbal flavor in the coffee, and has much more variability in taste, and risk of “off” flavors in the final coffee. In Brazil, the largest global coffee producer, the vast majority of coffees are natural process, while in Central America, Bolivia and Peru, the majority of specialty coffees are washed.
In order to maintain its commitment to only buying highest-quality coffee, Invalsa tests samples from every single bag that it purchases from every farmer before accepting the bag. The process that coffee buyers use to evaluate the quality of coffee is through a controlled tasting, similar to a wine tasting. This process is called coffee cupping.
Coffee Cupping and Grading
In order to evaluate a coffee and compare it to others, coffee samples are all roasted to the same roast level, ground to the same particle size, and prepared with hot water in special cupping cups. Typically three or four cups of each coffee will be prepared in order to increase the chances that a problem in a particular batch of coffee will be caught. Cups will be labeled only with numbers, rather than farmer names, so that the cuppers tasting the coffee will be tasting “blind” and will not be influenced by knowing where each coffee is from.
Cuppers use a standardized cupping form to evaluate each coffee on a 100-point scale. They evaluate factors including aroma, body, mouthfeel (creamy vs. thin), clean taste, flavors, acidity (brightness of flavors), aftertaste, and consistency. This photo shows Nelson and some of the guest roasters on Invalsa’s 2012 Bolivia Origin Trip, cupping coffees in Invalsa’s offices in La Paz, during the October 2012 origin trip.
A score above 80 points is considered a specialty coffee, while a score above 85 is considered worthy of separating into a special micro-lot from one particular farmer. Invalsa grades, or categorizes, all of its coffees into four grades, based on cupping score: Premium/A (78-79 points), Superior/AA (80-83 points), Cumbre/AAA (84 points), Supremo/A4 (85+ points). These grades are based only a cupping scores, not coffee bean size or any other factor. It is assumed that the larger and denser beans are better, but there isn't actually scientific proof for this.
Cup of Excellence
The Cup of Excellence is a series of competitions organized by a US-based nonprofit called The Alliance for Coffee Excellence (based in Montana) in many coffee-producing countries in Latin America and Africa every year. You can learn more at their website, www.cupofexcellence.org, but we will provide a summary because Invalsa is often involved in COE competitions and offers many COE coffees to customers.
A COE competition takes place every year in each participating country. Before the competition, farmers from that country submit samples of their best bags of coffee to be evaluated by a national jury, which selects up to 60 coffees to be included in the competition. During the competition, an international jury of some of the world’s best coffee tasters evaluate these coffees over five days of repeated cuppings, and narrow down the lots to the best coffees, all scoring an average score of over 85. The coffees that make this cut are then certified “Cup of Excellence Award-Winning” coffees, which means they can be sold with a special sticker and are listed on the COE website.
One week after the competition, there is an international online auction lasting for one day, where Alliance for Coffee Excellence members can bid against each other to buy the COE coffees. The top-scoring coffees can easily sell for over $20 (sometimes over $50) per pound. Check out the COE coffees that we currently have available: green (if you're a coffee roaster) or roasted (if you're a coffee drinker)!
Nelson has participated as an international judge on COE juries in almost all of the countries that have COE competitions: Bolivia, Brazil, Colombia, Costa Rica, Guatemala, Mexico, Rwanda, and Burundi. Every year, Invalsa participates in COE auctions, and often puts together ‘buying groups’ of smaller coffee roasters that may not be members of the Alliance for Coffee Excellence (so they cannot bid directly themselves) in order to share lots of COE coffees.
Unfortunately, since 2009 Cup of Excellence competitions are no longer held in Bolivia due to the Bolivian government’s opposition to accepting American aid money to pay for the competitions. Jorge Valverde was the coordinator of the last two COE competitions in Bolivia, which were very successful, and most of the farmers that Invalsa works with were former participants in the COE.