Hi, my name is Thomas Eagley. I'm the director of the Epileptic School of Herbal Medicine and the co-author of the Modern Herbal Dispensatory. And today I'm with Mountain Rose Herbs and we're going to demo how to do an herbal percolation.
Percolation is one method to make... herbal tinctures. The other most common method is maceration, where you stick things in a jar and cover them in alcohol and let them soak.
They normally take three to six weeks of soaking with daily shaking to get to all the constituents. that are in the plant into your solvent, into your alcohol water mixture. Percolations are convenient because they're normally done in like 24 to 48 hours.
They take a little bit more work, but they're not quite as complicated as a lot of people. think. So let's dive right into it. For percolation, you're going to need a percolation comb, and you can pay a scientific glassblower a lot of money to make one for you, or you can use a wine bottle that you've cut the base off of.
A lot of people do the string and fire method to get the bottom off in their glass cutters. What I found is that a wet tile saw works really well to make a smooth cut that there's no chance of, you know, getting an edge that's going to... cut you. The wet tile saw you could buy new, but probably you have a neighbor that's remodeled their house and installed tile flooring and borrow one from a neighbor. Cut the bottom off.
I like the one and a half liter. wine bottles because you can get your hand in there so they're easier to clean. Once you cut the base off, the other side is going to be a way to control your flow rate.
And a lot of people use instead of wine bottles, they use water bottles with an adjustable lid and they control the flow rate by tweaking the lid a little bit tighter, a little bit looser. One of my friends, Darrell Patton from Alabama, figured out that you could use a needle valve that you can purchase at most hardware stores. And I played around with a lot of different stoppers and found a food grade silicon stopper that works well.
So we're going to use this to control our flow rate. Then you need a container to catch your tincture in and you need some weight to hold that. You can just take your percolation cone and set it right into a jar.
then you have to move it up every time you need to adjust your flow rate with your valve. And so what I recommend is getting a lab stand. You can pick one up for about $30. And it's like getting an extra set of hands, which is really helpful when you're preparing herbs.
So what we're going to do today is make a percolation of Echinacea angustifolia. All percolations are... are done with dried powdered herbs. You can't percolate fresh herbs. So we're going to get our powder.
See? Extra set of hands. We're going to take our herb powder and we're going to weigh it out because unlike the folk method, when you are doing percolations, you're going to go with a weight to volume ratio.
A standard weight to volume ratio is 1 to 5. That means 1 gram of plant material that's dried and powdered and preferably seeded through like a number 60 screen. 1 gram of that. per 5 milliliters of whatever solvent that you're using.
In this case, we're going to do a mixture of water and alcohol at a 50% alcohol volume. So, in a 1.5 liter wine bottle, magnum wine bottle size, you can get about 100 grams of herbs with enough space left for your minstrel. So, we're going to weigh out 100 grams.
There we go. So. If we were to dump this dried herb powder into our percolation comb, once our water-alcohol combination hit it, it would swell up and would not let fluid flow through.
So we have to pre-moisten our powder and we do that with the same solvent that we're using, in this case 50% ethanol. The technical way to do it is to take your powder, put it into a volumetric flask, compress it, see how much it... displaces and then you're going to pre-moisten with about 65% of your displaced volume. We're just going to eyeball it because we're going for a specific consistency of wet sand. So We take our minstrel and we add a little bit in.
And then we give it a stir. And we're just trying to rehydrate our powder. so that the cell walls expand to their kind of maximum size and it doesn't swell once we add our minstrel in.
So this process of adding a little bit of your menstruum and then working it in and making sure that it doesn't swell or that it is fully swelled, that it's not still dry. This takes experience. I recommend the first few times you make percolations, use the cheapest powdered herb you can find so that if you mess it up, you know, you haven't just tried to percolate 500 bucks worth of American ginseng root.
Use something maybe that you have left over or that's inexpensive and play around with this process. So we're getting to a pretty good consistency. What you'll find when you're pre-moistening your plant material is that things will look really good, and then you'll come back like 20 minutes later and it's sucked in more water. So you have to keep adding and tweaking for the first hour or so to make sure that it's the right consistency.
And once you get things looking the right consistency, you want to put something over the top to prevent your minstrel from evaporating. and then let it sit and just soak in and hydrate for at least two hours. A lot of people say 12 to 24 hours.
I normally, you know, two or three hours and we're good. So this will need to sit aside and make sure that it's absorbed all of the moisture. I have already pre-moistened. Another batch, and this is the consistency that we're looking for.
It is wet sand, like it clumps in your finger but falls apart pretty easily once you drop it. So we have our echinacea that has been pre-moistened. It's at the right consistency.
Now we're going to pack our cone. A lot of times when you pack, when you do percolations or see classes on percolations, they'll put a coffee filter in the bottom to hold the plant material up. And I did it that way for years. And then maybe a year ago, somebody said, why don't you just use cotton balls instead?
So you can get these unbleached organic cotton balls and just shove them in the neck. of your percolation column and that will hold your plant material off of the bottom and allow some space for fluid to fill. Then we're going to put our valve in and you want to be sure with these silicon valves, because they're pretty slick, that you really press it in there.
And then we're going to open our valve up because as fluid moves through it's going to displace the air and if we keep our valve closed those air bubbles will come up and disrupt our packing of our pre-moistened herb. So we're going to open that up until everything runs through. Then we're just going to This down and start adding our plant material.
This is done in thirds. You're going to dump about a third of your plant material straight into your percolation cone. And once you get about a third of your plant material in there, you need to slightly compress it. So we're going to tamp it down.
And what we're doing here is just making sure that the consistency... of the powder is even because we want an even movement of our minstrum through our plant material. If you over pack, if you tamp down too hard, then your fluid won't be able to make it. way through. If you tamp down too loose then your powder will, once you add your menstruum, will kind of float, which is not great.
So it takes practice. I've been doing this for years and I still mess these up every now and then and I pack them too tight or I don't pack them tight enough. But Once you get the hang of it, it's pretty easy to stay consistent.
So we have that packed in now. We've got 100 grams. And we're going to do a 1 to 5 extract.
So we're going to add 500 milliliters of our solvent. So if we just add it right now, it's going to disrupt the packing. And all of the plant material will start to float around. And you won't get an even movement of your solvent through your plant material.
So we're going to take an unbleached coffee filter. and put it in and just kind of press it in place so that when we add our solvent our powder won't float to the top. Now what you're looking for is an even movement of your minstrel through your plant material.
So keep an eye on the moisture level as it moves down and it should be moving. At about the same speed all the way around. If it's not, then I have kind of packed it unequally.
That looks good. You can see the minstrum flowing through evenly through the plant material. And it is about two-thirds through now. Remember that our valve is open.
Now at this point, if your valve is closed, all of the air that the fluid is pushing will bubble back up and you'll get little rivers through your powder and you won't get an even movement of your solvent. So keep the valve open until you start getting your solvent dripping through, your minstrel dripping through the bottom. We're down to about here.
One of the benefits of percolation is that you're moving unsaturated solvent here at the top through the plant material and extracting the stuff that's inside of plants. works via a constituent or a concentration gradient so your your menstruum will only pull out half of what is inside the cell walls of the plant. But because our minstrel is unsaturated as it moves through, it's going to pull a little bit more than if we did a standard maceration. Now, there's no studies on this that I'm familiar with, but the general consensus is... that percolations, which can only be done with dried herbs, so there's some drawbacks, but percolations are somewhere between like 10 and 30 percent to more potent than standard macerations.
I definitely have plants that I prefer doing standard macerations on, but the majority of the dried herbs that we turn into tinctures, I like this process of percolation. So we moved all the way through the plant material. Now our cotton balls, our filter, is slowly filling with our liquid. There's the first one. So we're going to get ready as it filters through to close our valve once all of that air has been displaced.
And of course if a few drops go through it's no big deal. But the idea is to... here we go.
Our liquid's at the bottom, the air is displaced, it starts to drip, and we just close our needle valve. Now, at this point we pause and we let this minstrum sit with our plant material for about 12 hours. And that process is called digestion. And once our plant material has been digested by our minstrum, that means that the solvent, the minstrum that's in contact with the plant material has had enough time.
to pull the constituents from inside the cell wall out into solution. Once that 12 hours has passed, we're just going to start our percolation dripping. So let's just pretend that 12 hours has passed.
We're just going to adjust our valve so that we get one drip. every three to five seconds. So, a slow, steady drip of about one droplet every three to five seconds.
And this is, you know, set overnight and digested. This is going to take a couple of hours to move. the continual unsaturated solvent through the plant material and then in a couple of hours your tincture is ready.
So percolation, fairly easy to do. You do need to do a little bit of of weighing and measuring to make sure that you have a good weight to volume ratio. One to five is the most commonly used one.
You can do one-to-one fluid extracts with a few extra steps. And once you've weighed and measured everything, pack it in thirds. Remember to keep your valve open until it starts to drip.
Close it off, let it sit 12 hours, and then open it back up so you get one drip every three to five seconds. seconds, you'll have a finished tincture ready to go within about 24 hours of starting this whole process. And that's how you make percolation-based tinctures.