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they will do a practice more similar to Ethiopia. I, however, have never seen a year when conditioning bins are not used at all if the washing station has them. • BURUNDI/RWANDA — In Rwanda and Burundi, not all but many of the washing stations start out drying the coff ee on raised beds under shade. T is is done for one or two days. T is practice is believed to help protect the parchment due to slower drying for the fi rst day or two when the coff ee is at its highest moisture. In Rwanda, once pre-drying is complete it is done more or less normally, like in Ethiopia, and takes around 14 days. In Burundi, however, many of the washing stations have adopted what is called Pyramid Drying. T is technique involves the coff ee being placed on the raised beds in small stacks, or pyramids, for the fi rst eight to 14 days to reduce the drying surface area. As time goes on, the pyramids get bigger, slowing the drying time even more. T is very slow drying technique can easily push coff ee to 16, 20 or even more days to dry. • LATIN AMERICA — While raised beds are not especially popular in Latin America, they are used, and many producers are building raised beds for experimentation. (Raised beds are popular in Latin America when used in solar dryers, but I'll talk about those under that category.) Most places in Latin America that use raised beds do turn the coff ee frequently for even drying; they generally are not covering mid-day, or doing pre-drying. T is method, combined with warmer temperatures in many places where the coff ee is dried, makes drying times generally around nine to 12 days in Latin America, when not in solar dryers. SOLAR DRYERS Solar dryers are generally raised beds that are surrounded by a clear plastic enclosed covering, like a greenhouse. T ey are also mostly popular in Latin America, but I have seen them around the world. Inside of the solar dryer, raised beds are oſt en stacked, but not always. In the case of stacking the raised beds, coff ee is generally placed on the lowest rung and moved up as it slowly dries. Solar dryers are oſt en used in places where it can rain frequently during the drying season, so it's helpful to have the clear plastic to protect the coff ee from the rain. T e clear plastic tent surrounding the coff ee, depending on how open the sides of the covering are leſt , creates a greenhouse eff ect and can create very warm temperatures. In some circumstances, the coff ee can dry in three days. But if the plastic is leſt very open, the coff ee can easily take up to two weeks or more depending on weather. I have also seen solar coverings used on top of patios, but that is very rare. MECHANICAL DRYERS In recent years mechanical drying has become more and more popular, especially as wet and dry sessions become less predictable and drying becomes harder. Mechanical dryers are again generally found in much of Latin America but increasingly outside of the Americas, as well. While there are certain commonalities among most dryers, style ranges widely. Here are some that I have seen: • DRUM DRYERS — Mechanical drum dryers are the most common dryers I have seen in my travels. T ey work off of a fl ame generated by gas or wood that is then fed into large turning drums with multiple compartments that coff ee can be put into. In essence they look and work a lot like a coff ee roaster at temperatures that range from 90 to 160°F. In general coff ee is dried in one or two days. • STATIC DRYERS — Static dryers look like large metal boxes that trays of coff ee are put into and hot air circulates through—think convection oven. Like drum dryers, static dryers are kept at temperatures ranging from 90 to 160°F, and have drying times in the one to two day range. • PAN DRYERS — Pan dryers look almost exactly like the cooling tray on a coff ee roaster. T e major exception is that the hot air is pushed up through the screen and then through the coff ee, as opposed to room temperature air being pulled through the coff ee and the screen. T is, just like a cooler on a roaster, happens while the coff ee is being turned by moving paddles. Drying time again is usually one to two days. With drying, it's easy to become dogmatic when talking about diff erent methods, and on the surface it is easy to criticize one method over another. I actually fi rmly believe that every method I have seen can result in a great, durable coff ee. However, I will happily also say that some methods are easier to create that durable product with, and in general, slower, more even drying techniques are better. I think a good reference that most people in the industry are familiar with is tasting one-year-old African coff ee and being blown away by how OTHER PROCESSING NOTES ANAEROBIC FERMENTATION T is basically means fermentation in the absence of free oxygen. While I have seen and heard of a few places using airtight buckets that are closed during fermentation, I still do not think this denotes anaerobic fermentation, and to this day I have yet to see any operation that employs oxygen free fermentation as I understand it. I am sure some experiments have been done, but I have never tasted or seen these in operation in my travels. POST FERMENTATION SOAKING T e most popular and repeated commentary you'll hear about post fermentation soaking is that it changes the amino acids of the coff ee based on speeding up germination. T is comes about from the fact that agronomists and nurseries use soaking of the parchment as a way to speed up the growth of the coff ee from seed. I was told by an agronomist that the seed more or less thinks it will drown and die in the water, so it tries sprout faster. Whether or not this happens at a rate to radically alter the coff ee I cannot speak to nor have I seen any scientifi c documentation about, so I can neither confi rm nor deny this assertion. T e other observation I have heard more than once is that by doing a post fermentation soak you lose one-half to one-and-a-half percent of your parchment weight. T is again creates speculation that soaking might take out some of the lesser bonded cellular material which then lead to those juicier qualities. While I cannot speak to the chemical and cellular ideas associated with soaking, I can say that in multiple experiments around the world, it does create a diff erent tasting product when used. little the coff ee has faded over such a large amount of time. I think it is oſt en overlooked that most of those coff ees are dried an average of two weeks, compared to patio-dried coff ees that are proclaimed "done" at fi ve or six days. T e same goes for mechanically dried coff ees that spend one or two days between wet and dry. When I think about the one-year-old African benchmark, it's hard not to give a lot of credit to raised beds, or at least a slower, more even drying style, whether it is the sole reason for the longevity or not. For me personally, I believe that issues with drying and with how the dried coff ee is stored and handled, are the largest culprits when quality degradation in the cup is present. All too oſt en, beautiful amazing coff ees fade to unrecognizable, fl at, dry, boring, and marginal refl ections of their former selves in just a few months. All of those issues were likely preventable at some stage aſt er fermentation and washing. Today though, with a mindfulness of diff erent drying techniques, coupled with more advanced meters to monitor water and water activity inside the coff ee, it looks like drying and the interest in producing a long- lasting product have and are continuing to make large steps forward. www.baristamagazine.com 49