In Part 1, I explained how to harvest and prepare the beans for curing, and what equipment you’ll need. Next, we’ll go through how to sweat, dry and age the beans.
The Sweat Cycle
Following from the previous tutorial, your beans are now in the warm sweat box.
The beans are going to stay in the sweat box for 48 hours at first. Use the thermometer to watch the temperature in the zone where the beans are. The optimal temperature is 115℉, so the closer it stays to that temp, the better. Lower temperatures are OK, but once it gets into the low 90s, refill the water jugs.
This may be the most challenging part of the process to get right, but remember that having it drop into the 80s is not a big deal, it just will slow things down. Do your best to keep the temps up, but don’t worry about it.
The beans will become sticky and wet in the bag. This is what we’re looking for, it’s the sweat.
Once the 48 hours (or so–no need to be exact) is up, we cycle the beans through the dehydrator. Take your beans out of the bag and spread onto your dehydrator shelves. Turn the dehydrator to 115℉ and leave the beans in there for an hour or so. The stickiness should dry some…probably not all the way dry for the first few cycles.
Refill the hot water jugs with hot water.
After the hour of dehydrating, put the beans back into their bag (don’t be tempted to replace, wash or dry the bag, just re-use the wet bag), and then into the sweat box.
While the first sweat cycle is 48 hours, all subsequent sweat cycles will be 24 hours until the sweating is done. Between each cycle is 1 hour in the dehydrator. The effect of this is a very slow drying while the beans are sweating. This is partly to prevent rotting with all that warmth and moisture.
Once you’re into the sweat by a week, it becomes less critical that you do the dry cycle every 24 hours. Skipping a day is not a big deal. The temperature needs to stay near the optimal 115℉ as much as possible the whole time, however.
In our operation here, we use a electrically heated sweat box, much like an incubator, so the temperature control is automatic.
Completing the Sweat
The sweat is going to take 18 days from when you first put the beans into the sweat box. In that time, the color will turn from green to a light greenish brown and finally to brown. The aroma of the beans will go from sharp and floral at first, to a kind of (what I call) “leathery” smell. It won’t so much smell of vanilla until the end of the sweating period.
The beans may be a bit oily (the “oil” is really glucose) to the touch at the end of the 18 days, and they will have begun to shrink and get longitudinal wrinkles. These wrinkles are something you are going to focus on when assessing the progress of a bean as it cures.
Drying the Beans
The next stage is slowly drying the beans until they reach the desired moisture level. This can take anywhere from 3 weeks (for smaller beans) to 2 months to complete.
How you do the drying depends on what situation you can arrange for the beans. Here in Hawaii, we dry them outdoors on a drying rack that is elevated (on a roof) and protected from the rain and sun. Depending on your circumstances, there are several ways you can do the drying.
We want to dry the beans very slowly to get the best quality. This allows any remaining vanillin reactions to complete within the bean. It also helps ensure that we don’t overdry the beans. The sweat has conditioned the beans so they are preserved and stable as far as spoilage is concerned, so we are not in a hurry to dry them.
The important considerations for drying vanilla are:
- Clean, dry environment
- Undisturbed for several weeks
- Plenty of air circulation
Here are some ideas for setups for drying the beans:
- Indoors on dehydrator shelves placed on a laundry rack or wire shelf
- Outdoors on a similar setup, but away from the ground or over concrete, such as on a patio. Keep them high off the ground and don’t let the drying beans get wet.
- Solar dehydrator not in the sun, similar location: high off the ground or over concrete, this is to avoid dew, which comes up from the ground.
- Dehydrator with fan on and heat off. Drying will happen much more quickly, watch them closely.
Checking the Beans’ Moisture Level
The drying process will need to continue as long as it takes for each bean to reach the desired moisture level. Each bean will dry at its own rate, so you will need to check on them frequently. Beans that are done are put into a sealed plastic bag.
To check the moisture level, look closely at the wrinkled surface of the bean. While a bean is drying, there will be wrinkles with smooth bean surface between them. As they dry, the width of the smooth surface between the wrinkles gets smaller. A fully-dried bean will have little or no smooth areas between the wrinkles: it will be all wrinkles.
You can feel the dryness as well. This takes some experience to get right, but you can squeeze the bean between your fingers to get a sense of what the moisture level inside is. What I look for is something like what you’d expect a soft dried fruit (such as an apricot) to feel like. As it dries, it will stop feeling slippery inside the bean and instead it will be a little firm yet still supple.
The color is another way to gauge the dryness: it will get darker, usually going from dark brown to almost black. This is not a reliable test, however, as it is normal for the bean color to vary depending on a lot of factors. Your beans may start out light brown and get darker, but only to a dark brown.
If the beans stay light brown, that is a quality issue. They will feel slightly hollow inside and dry on the surface. A bean like this is till usable, but it won’t have the flavor intensity of a good quality bean. The usual reason for this condition is an under-ripened bean.
Conditioning the Beans
Once the beans are dried, the final stage is to age or “condition” them for a while. As explained above, we place the dried beans in a sealed plastic bag as they dry. Label the bag with the date of the least bean to go in there.
The beans will condition for at least 3 months after drying. This is where the flavor and aroma settles in and stabilizes. Since the beans are together in a sealed container, the moisture and aroma equalizes between the beans, and you end up with a more consistent cure.
After the 3‑month conditioning, the beans are done and can be handled like any vanilla bean. They should be kept in a sealed container and will keep indefinitely that way. This is also when you will select out your beans for making extract.
Extract beans tend to be dryer, so select out all the beans that are firm, and not as supple. Also any small beans or beans that are split more than 1/2 inch. These beans are used to make your extract.
So that’s it, if you’re growing vanilla, you can use this tutorial to cure them for maximum flavor development while preventing mold.