Just a reminder, we won’t be at this week’s Noe Valley Farmer’s Market due to some machine issues.
After spending most of the day looking at the trees, pods, and harvesting, we spent the last part of the afternoon looking at the bean drying process. After the beans have been fermented (we were too late to see that part this day, but we’ll cover it in another post), they have to be dried. Bean genetics, fermentation, and the environment where the beans are grown play a large part in determining the flavor. Drying can’t be ignored, though, as it also has a big impact on the final flavor. Here are some beans drying on the concrete on their first day post-fermentation:
To make sure the beans are spread out evenly and don’t clump up, the workers draw coarse rakes over the beans:
As Bertil explained, the first part of drying is to stop fermentation of the beans. Since fermentation generally takes place between 47 C and 52 C, you can either cool the beans down (e.g. by washing them) or heat them up (e.g. by putting them on hot concrete). Concrete works well because it’s hot (but not too hot) and it’s less likely to stick to the still wet beans. Usually, after a day or maybe two of limited drying on concrete, the beans are moved to the mobile wooden drying beds:
The other part of drying is, not surprisingly, letting moisture, both water and acetic acid, out of the bean. How much acid you let out has a big impact on the flavor, with some makers preferring a more acidic taste and others preferring a more mellow flavor. You can control how much acid stays in the bean by varying how long the beans are left in the sun. Counterintuitively, the longer the beans are left in the sun, especially early on, the more acid stays in the bean. This happens because the outer shell of the bean dries first which then prevents any more acid from escaping. By getting the beans out of the sun sooner, the outer shell stays wet and the insides can keep drying. The great thing about visiting the farm and working with the farmer directly is that we can provide input on the drying process in order to get the flavor we want!
Once the beans have been out in the sun long enough for the desired flavor, they’re gathered up and moved inside, where they’ll rest (and continue to dry) until they’re moved back outside the next day:
It depends on the weather, but drying often takes about a total of seven days.
Since all of the other pictures in this post are mostly brown, here’s a picture of the delicious mango (from the tree outside Ivan’s house) I had for breakfast: