Showing posts with label making a tincture. Show all posts
Showing posts with label making a tincture. Show all posts

Thursday, March 6, 2014

Making Medicine Part 5 of 5: Pressing and Filtering a Tincture

This is the fifth and last post in a series in which I am using the process of wild harvesting and making a fresh herb tincture of blue vervain (Verbena hastata) as an example to explain in detail the process of making herbal tinctures. In Part 1 of this series I discussed the process of harvesting blue vervain; in Part 2, preparing the herb for macerating; in Part 3, preparing the maceration; and in Part 4 I discussed some of the common equipment that is available for pressing and filtering the maceration. Now we're going to look at the actual process of pressing and filtering our maceration to prepare the tincture.

As I indicated in Part 4, this final stage in preparing our tincture can be either a single or two part process. The standard method is to pour the maceration into our press. Much of the fluid (also called the macerate) will flow through, but not all of it. Then we apply as much pressure as our press will easily allow to squeeze as much of the fluid as we can out of the herb material (also called the marc). The better the press, the more fluid that we can press out of the herb. This is not only more efficient because we will end up with a greater volume of tincture, but our tincture will tend to be a bit stronger because the fluid that is deep withing the tissues of the herb will tend to contain the highest concentration of its constituents. Having macerated the herb for at least three months will ensure that the herb tissues have softened sufficiently to make it more easier for our menstruum to penetrate into the tissues of the herb, extract its chemical constituents, and be pressed out when we apply pressure.

With this method, the fluid that flows from the press will contain herb particles that are small enough to pass through. The fluid must then be filtered. The standard method is to allow the tincture to flow into a filter in a funnel placed over a large beaker or other kind of receiving container, and allow gravity to draw the tincture through the filter. Beakers are the best container to use because they have a large opening, are graduated, have a spout that will make it easier to pour the tincture into our bottles, and better ones will be made of borosilicate glass which is more durable. Although the graduations on a beaker do not allow us to accurately measure the volume of our tincture, they give us an approximate volume which allows us to determine the size and number of bottles we will need to store it.

For this process we do not want to use a paper filter as these are too fine. We need to use a fairly coarse filter because we want to include the fine sediment and other thick components like latex in our tincture. This means that it is best to use a cloth filter. It is critical that our filter does not contain lots of chemicals that are typically found on fabrics these days. The best fabrics are unbleached organic cotton, hemp or another natural fibre or combination of fibres. Muslin or some other coarse weave is best as long as it isn't fuzzy like flannel. Otherwise cloth fibres might end up in our tincture. Even when using a relatively non-toxic fabric to make our filters, it is best to wash them a few times and rinse them very well. We don't want soap in our tinctures! Cloth filters will last many years. They need to be scrubbed (by rubbing the fabric against itself) and rinsed well after use. Although it is best to use soap the first time we wash them and rinse them very well, water alone is best after their initial use. Soap isn't necessary because tinctures are sterile. However, it is important that the filters be allowed to dry completely before storing them.

When using a potato ricer, the macerate (fluid) and herb material are poured into the ricer, which is held over the filter.
The liquid will flow through into the filter. An cone-shaped unbleached cotton coffee filter works well for this.

The herb material (marc) is then squeezed to get as much liquid out as possible. Once the macerate
has completely flowed through the filter we wring it out to get any remaining fluid out of it.

In terms of funnels, the best funnels have a design that has a spiral cut into them. This reduces the surface contact between the filter and the funnel and allows the fluid to flow out more quickly. These funnels are usually make of glass or polycarbonate (plastic #7). We don't want to use polycarbonate plastic because it contains toxic chemicals that will leach into our tincture. That leaves the glass ones. However, they are very expensive, easily broken, and only marginally speed up the filtering of tinctures that have sediment or latex. Tinctures that don't have these components tend to filter relatively quickly anyway. As a result, I recommend solid plastic funnels. They are inexpensive and easy to obtain. That being said, we only want to use funnels that are made of polyethylene or polypropylene (plastics #1, #2, #4 and #5) as these are not known to contain any chemicals that will leach into our tincture (so far). If the funnel doesn't clearly indicate which type of plastic it is, don't use it.

With a screw press, the receiving cylinders must be removed from the frame of the press in order to
be able to easily empty the contents of our macerating jar into them. It is also important that
the beaker be at a lower level to allow the tincture to flow into it.

The biggest disadvantage of this method of filtering is that it is very slow. In fact, if the tincture contains a lot of sediment and/or latex it can be extremely slow, even with a very coarse filter. This is undesirable because the longer our tincture is exposed to light and especially air, the greater the amount of degradation of its active constituents that will occur. As a result, I always use the second method of filtering the macerate and that is to make cloth filters that fit inside our pressing device. This allows the maceration to be pressed under pressure. It only slightly slows down the pressing process and the end result is a filtered tincture that can be bottled immediately. The reduction in time will significantly reduce the oxidation of the components of our tincture and therefore improve its quality and how long it can be stored before use. With this method it is not necessary to use a funnel unless we are using a potato ricer as our press. With a well designed screw press or hydraulic press the tincture can be directed directly from our press into the beaker.

With a potato ricer the cotton coffee filter is placed inside the ricer. It's still a good idea to use a funnel because the tincture
doesn't flow out of the ricer as neatly as through a hose and the funnel provides a wider area for it to drain into.

Here's the same set-up with a screw press. In this case it's necessary to make filters that fit the inner cylinder
of the screw press as cotton coffee filters are too small and not the right shape.

We pour the fluid into filter and then empty any of the remaining herb material into it as well. There will always be some residue in the jar, so I will pour some of the filtered tincture back into the jar to rinse the last of the herb material out of it. then we fold up the top of the filter so that when we apply pressure to it none of the unfiltered fluid will flow out of the top. With herbs that have a latex or are very mucilaginous, the filter will sometimes clog up preventing the fluid from draining efficiently. If this happens, it is important that there is no excess liquid on top of the herb material in the filter when we press it or it will not be possible to prevent it from flowing unfiltered out of the top of the filter. In this case I lift the filter part way out of the cylinder and rock it back and forth to speed up the rate at which the macerate flows through. Once the level of liquid is below the top of the herb material, it is OK to fold up the filter over top of it and press it. With a potato ricer we simply press it as hard as we can; with a screw press we tighten the screw as tight as we can; with an hydraulic press we pump it as much as we can.

Tightening the screw.

Here's the actual process using my hydraulic press: pouring the macerate and herbs from the jar into the cylinder.

Pumping the press.

With this method, once we finish pressing the herbs the filtering process is also complete and our tincture is ready! We need to get our tincture into bottles as quickly as possible in order to minimize oxidation. It is necessary to use narrow mouthed bottles because they have a smaller air space and it's easier to pour out of them. Once more we want to use amber glass bottles. The bottles I use are called amber metric rounds. The best lids are plastic phenolic caps with a cone-shaped polyethylene liner as these lids seal the best and polyethylene is one of the two kinds of plastic that are suitable for this purpose (the other being polypropylene).

50 ml, 100 ml and 250 ml amber metric rounds. The equivalent in the US is 2, 4 and 8 oz. bottles, which are slightly larger.

It is better to store our tincture in several smaller bottles rather than one large bottle. This will significantly increase the shelf life of our tincture. Every time we open up the bottle and use some of it we are exposing it to more oxygen and increasing the size of the air space in the bottle. The tincture in the bottle we are using will degrade much more rapidly than tincture in a full, unopened bottle. Since I tend to press half or one litre jars, I store my pressed tincture in multiple 250 ml bottles. If you are making smaller quantities for personal use, it is better to store your tincture in 100 ml bottles. Just like with our maceration, these bottles should be stored in the dark. Presumably, the last one we fill won't be completely full. We'll start by using that one and not start another until it is completely finished. In this way each bottle remains undisturbed until we need it. For most herbs, the tincture stored in the dark in an undisturbed full bottle will maintain its potency for about 6 months to a year. However, once we start opening it and using it it's best to use it up within 4-6 months. They don't go bad. They just lose their potency. The timing I have indicated is what is ideal. It doesn't mean you should throw out a tincture if you don't use it all within that time frame. However, I like to do things as ideal as possible, so I usually don't press any more of a specific tincture than I can use within 4-6 months.

Pouring the finished tincture into storage bottles. For demonstration purposes I broke with the tradition of these posts. I did not press
blue vervain herb tincture (Verbena hastata) because I had plenty on hand. Instead I pressed a half litre of blueweed herb tincture
(Echium vulgare) which is from the Borage family and has similar properties as common comfrey herb (Symphytum officinale).

It's important that we label our bottles of tincture. The label should include the name of the herb, the part of the herb used, the potency of the tincture, and the date it was pressed. I always use the same bottles for the same tincture because the bottle picks up the aroma and energy of the herb. You will note from the photo that I use green masking tape for labels because it is relatively water resistant, can be written upon and looks pretty good. Each time I press a tincture I cross out the old date on the bottle labels and write the new one until the label is full. Then I start a new one. This is an efficient way to label them because the same label can be used many times and a quick scan of the label gives me an accurate indication of how much I am using that tincture. This information is important when it's time to harvest that herb in terms of estimating how much I will need for the following year.

So, that finally wraps up this discussion of making tinctures! I hope that you have found it useful. As I promised way back when I posted the first installment of this series, since blue vervain was the common thread, especially in the first three posts, I am providing detailed information on the properties and uses of this herb that is based on my research and experience on the Herbal Resources page of the Living Earth website in the form of a pdf document that you can download (link to pdf file). Enjoy!

Thank you blue vervain!


Wednesday, August 22, 2012

Making Medicine, Part 3 of 5: Making a Fresh Blue Vervain Maceration

This is the third in a series of five posts in which I am using the process of wild harvesting and making a fresh herb tincture of blue vervain (Verbena hastata) as an example to explain in detail the process of making medicine. Part 1 of this series was posted on July 9th, Part 2 on July 15th. This series started as a single post, then became two, then three, then four, now five. As it progresses I realize that there is a lot that needs explaining. I have decided to do that thoroughly so that I can reference it from future posts rather than having to repeat information.

In the second post in this series we got up to the point where the blue vervain had been chopped up and was ready for making a fresh herb tincture. Now we are going to discuss making a tincture in detail. This is essentially a two part process. The first part of this process involves macerating the herbs. Maceration is the technical term for soaking the herbs in our extraction medium or menstruum. This will be the focus of this post. I will address pressing and filtering the maceration to make the tincture itself in the last post.

I discussed the important issues concerning wild harvesting and preparing blue vervain for macerating in the first two parts of this series. The next step is to put the chopped herb into a jar. This requires two things, a funnel and a jar.

The kind of jar that we use is very important. Firstly, it needs to have a wide opening so that it is easy to get the herbs into it and out again when it is finished macerating. Secondly, it is preferable that the jar is made of dark coloured glass. Amber seems to work best and it is less expensive than cobalt, which is the other major choice for dark coloured glass. Amber jars reduce exposure to light, which is one of the most important causes of degradation of the constituents of herbs. It is therefore important that we minimize the amount of light that our herbs and our maceration are exposed to. To accomplish this during the initial preparation, the herbs are chopped, put into a jar, covered with menstruum, and sealed as quickly as possible.

I know many herbalists who use Mason jars for macerating tinctures. This is probably because they are cheap and readily available. Some don't realize the importance of minimizing exposure to light. Others claim that the minimum light exposure that occurs while preparing and shaking their maceration is not significant as long as the jars are stored in the dark. It is very important to me to ensure that the medicines I prepare are of the highest quality and I am always experimenting with ways to improve this process. I have prepared two macerations of the same herb at the same time in the same way, one in an amber jar and the other in a Mason jar. Both were stored in the dark in the same location. I allowed them to macerate for the same amount of time and pressed them the same way on the same day. When I pressed the two macerations, the one that was prepared in the Mason jar was already significantly oxidized and the one that was in the amber jar had oxidized very little. You can tell that a tincture is oxidized because it is darker (usually more brown) in colour.

Once we press a tincture (which I'll discuss in the fourth and final post in this series), the constituents begin to rapidly degrade. There are a couple of ways we can slow this process down, but we can't prevent it. It is much easier to minimize this degradation during the initial preparation and maceration process. We can maximize the quality and potency of our tincture by minimizing the degradation of its chemical constituents up to the point of pressing it. This will also maximize its shelf life once it is pressed.

The final point that I would like to make about Mason jars is that, in order to prevent the lid from rusting, it is coated with plastic that contains bisphenol A (BPA), a hormone disruptor that readily dissolves into our maceration and accumulates in our body tissues. BPA has many known and probably many more unknown negative health effects. There are numerous sources of this environmental toxin and most people have significant levels in their body tissues and fluids. It's not something that we want in our tinctures! There are Mason jars out there that have a plastic lining that is "BPA Free", however, the BPA has been replaced by bisphenol S. BPS has similar hormone disrupting properties as BPA.

That brings us to the discussion of lids. Our wide-mouthed amber jars need a lid. Metal lids are not recommended because they either have a plastic coating that contains BPA or similar chemicals, or they have no coating and will rust. As a result, although I'm not a big fan of plastic, it is the best option as long as it's the right kind of plastic. The two options for lids that I recommend are high-density polyethylene (HDPE, ♴) and polypropylene (PP, ♷). Neither of these plastics leach BPA, pthalates or other known hormone disruptors. That doesn't mean that other toxins won't be discovered in the future that leach from these plastics, but at this point these are the safest plastic lids. If our lids don't have a liner, the softness of the plastic helps the jar seal when the lid is tightly screwed on, but occasionally it doesn't seal perfectly and our jar could leak a tiny amount. That also means fresh air (and more oxygen) getting into our maceration and increased oxidation of the chemical constituents. If we want the best seal, we need to use lids with a liner. Paper liners are not recommended because they will dissolve, and other liners such as polystyrene and polyvinyl chloride are toxic. The best liner is one made of low-density polyethylene foam (LDPE, ♶), also called an F217 liner. This is another plastic that is not yet know to leach any toxic chemicals. The last point on lids is that the liner must be loose, not glued in place, because the glue will also dissolve in our tincture. This also allows us to remove the liner for more thorough cleaning between uses. So to summarize, I recommend using a HDPE or PP lid either without a liner, or ideally with a loose (unglued) F217 liner.

The jars that I use are called amber round packers. These jars have a shoulder, which means that although they have a wide opening, it is not as wide as the full width of the jar like Mason jars. The volume of these jars is usually measured to the top of the shoulder and doesn't include the neck. Since when we macerate tinctures we need to fill the jar almost to the top, this kind of jar actually holds more liquid than the stated volume of the jar. The sizes that I use are 250 ml (8.5 oz), 500 ml (16.9 oz) and 950 ml (32.1 oz). However, when we fill these jars to 1/2 cm (3/16 inch) from the top, they actually contain 270 ml (9.1 oz), 540 ml (18.3 oz) and 990 ml (33.5 oz), respectively. I use the largest size for the herbs that I use the most and the middle size for the herbs I use less. The smallest size I only use for herbs that I haven't worked with. I will initially make a smaller amount of tincture that I use to do some preliminary research on the properties of the herb. Keep in mind that I am making tinctures for use in my practice and school. Anyone who is making tinctures for personal use will not require such large quantities. For personal use or for a family, making approximately 250 ml of tincture will be sufficient for a one year supply of most herbs. Rarely you might need 500 ml, but only for herbs that you use a lot. The amber packers also come in a 120 ml (4.1 oz) size, which actually contains 130 ml (4.4 oz) when filled correctly for a maceration. I recommend to my students to use the 120 ml and 250 ml sizes for most herbs for personal or family use, and only rarely the 500 ml size. Also, it is better to macerate a tincture in several smaller jars than in one large one. This is because, assuming that we make our initial maceration in a conscientious way, the greatest amount of degradation of the active constituents will occur after we press the tincture. So we don't want to press our tinctures in quantities that will require a long time to use. I recommend macerating tinctures in a jar size that will produce enough tincture to last about three to six months. I will discuss this a bit more in the fourth post in this series.

Amber round packers: 120 ml, 250 ml, 500 ml and 950 ml sizes.
Note wide-bottom funnel in the 250 ml jar.

Enough about jars, the last thing we need is a funnel. We need a funnel with a large opening at the bottom so that our chopped herbs can easily pass through it. The opening should be as large as possible, but narrow enough that the bottom of the funnel will insert at least two to three centimetres (one inch) into the neck of the jar so that it doesn't fall out easily. You can usually get a funnel with a wide bottom in a kitchen or automotive store, or department of a larger store. They are used for funnelling solids or highly viscous liquids like motor oil. If you can't find one you can always cut a regular funnel or make your own by making a cone from a piece of blank paper (no ink on it) or thin cardboard. Make sure you tape or staple it so it holds its shape and doesn't unravel while you are pouring something through it.

Glass funnels are best, but they are expensive and easily broken. Metal funnels aren't recommended because metal acts as a catalyst for oxidation reactions, which is problematic for chopped herbs because their inner tissues are exposed. Using a metal funnel will increase the rate of oxidation of the chopped herb material as it passes through. Once more, that leaves us with plastic. As with our jar lids, it is best to use HDPE (♴) or PP (♷). Polyvinyl chloride (PVC, ♵), polystyrene (PS, ♸) and other (O, ♹) miscellaneous plastics are not recommended because they are know to leach BPA, pthalates and other hormone disrupting toxins. Nothing that is made of these plastics should be allowed to come in contact with our herbs, maceration or tinctures.

At this point our blue vervain herb has been weighed to determine the correct amount that we need to make a 1:5 fresh herb tincture in a jar that holds 990 ml. It has been chopped to the appropriate level of fineness. Now we pour it through a funnel into a jar. If this is done too quickly, sometimes the herb will get stuck in the funnel. Tapping the funnel on the rim of the jar (with the end still inside the jar) will usually remedy this. If that doesn't work I will use the handle of a wooden spoon or a chopstick as a plunger to force the herb through.

Most herbs, if they have been chopped fine enough, will easily fit in our jar. However, some herbs are less dense because they have a lot of air spaces in their tissues. This is particularly true of many herbs from the Mint family (Lamiaceae). For herbs that don't easily fit in our jar, once more I will use the handle of a wooden spoon or a chopstick to compress the herb material in the jar so that it will all fit.

Once all of the herb is in the jar we need to fill up the jar with our menstruum. Traditionally, tinctures are macerated using a solution of ethanol (grain alcohol) and water. I'm going to begin this discussion by looking at alcohol. Back in the 80's, when the diagnosis of overgrowth of yeast (Candida albicans) became popular among many natural health practitioners and health food advocates, many people were promoting various anti-Candida diets that were based on a few common themes. One of the themes that emerged out of the general Candida concern was an anti-alcohol element. The basic idea is that consumption of any amount of alcohol will promote the overgrowth of yeast in our body. This led to some practitioners and authors of books on natural healing to claim that tinctures are not a good way to use herbs because of their alcohol content. This notion was further exacerbated by herbal manufacturers who, in attempting to capitalize on this trend, promoted the idea in their literature in an attempt to gain more market share by marketing the supposed alternative: glycerites or "glycerin tinctures". These are herb extractions that use some percentage of glycerin and water as a menstruum instead of alcohol and water. These concerns are unfounded. Firstly, because glycerin is actually a kind of alcohol. In fact, mold can grow in glycerin, but not in ethanol. Secondly, because glycerites are not a suitable alternative to tinctures. Glycerin is not as good an extraction medium or preservative for most of the chemical constituents of herbs. And finally, because the amount of alcohol consumed in a typical dosage of tincture is not in the least bit harmful, nor does it promote the growth of yeast. It is true that over-consumption of alcohol has a lot of potential negative health consequences, but the amount of alcohol consumed by taking tinctures, even at acute doses, is completely acceptable. The difference in the quality of tinctures versus glycerites is many times more significant than any potential negative consequences from consuming such tiny amounts of alcohol.

Other forms of liquid extractions of herbs such as acetics or "vinegar tinctures", which are extracted using some percentage of vinegar and water, have also been suggested as alternatives to tinctures. Although solvents such as glycerin and vinegar are good at extracting some of the chemical constituents of herbs, for the majority of constituents alcohol is better. Alcohol is also by far the best preservative for liquid extractions (not including toxic solvents such as methanol and benzene).

Before I go any further on this, I want to clarify two points that I just made. Firstly, the notion that yeast and other "parasites" are the primary cause of most health imbalances that people suffer from has been around a long time. It is called "germ theory" and it was initially developed by Louis Pasteur, a 19th century microbiologist. It is also one of the major limiting assumptions of modern medicine. As a result of the acceptance of Pasteur's theory into the reductionistic medical paradigm, medical researchers in the late 1800s and early 1900s looked for microbial causes of just about every illness and attempted to develop vaccines to treat them (this was before antibiotics). I am not suggesting that this approach hasn't resulted in useful medical treatments that have helped many people. However, the limitation of this theory is that it doesn't get to the root of the problem. In most instances, infectious diseases are caused by organisms that are in our immediate environment and often in or on our body all of the time. The major cause of illness is not the organism in and of itself, it is the lack of health and vitality of the person affected by it. This is directly the result of the dietary and lifestyle choices that we make every day.

Now lets fast-forward to the 1980s when Candida became a popular concern. Since that time many practitioners of natural healing disciplines have jumped on the germ theory bandwagon. It's the same old superficial approach, looking for an easy scapegoat instead of getting to the root of the problem. It is true that whenever there is an over proliferation of any microorganism, the presence of the organism will put additional stress on a person. Sometimes (but not always) it may be necessary to use treatment methods that directly affect the organism to help reduce the stress load on their body. However, using herbs to support the person's overall health and vitality and educating them about how the way they live affects their health and how they can improve on it is the essence of the treatment. And, for the record, in situations where it is necessary to directly address the "parasite", if herbs are our modality of choice, tinctures are usually the preparation of choice - and that means alcohol!

The whole issue of "parasites" is quite complex and maybe I'll do a post on it at some point in the future. For those who are interested, here is a link to an article that I wrote for the summer 2000 issue of Vitality Magazine (Dealing With Parasites). This one is too old to be archived on the Vitality website, so I have posted it on the Herbal Resources page of the Living Earth website.

The final point that I would like to clarify concerning this aspect of the alcohol issue is that, although it is true that the amount of alcohol in a typical dose of tincture isn't going to be harmful to most people or aggravate some condition that they have, I am not suggesting that the alcohol in tinctures isn't going to negatively affect anyone. There are people who have allergy-like reactions to alcohol. Also, some people who have a history of alcoholism are so sensitive to alcohol that the taste or smell of even a very dilute amount affects them in a negative way. However, collectively these groups make up a very small minority of the population. Although for them it will be necessary to use herbs in some other form, even though from a therapeutic point of view it may be somewhat less effective, for the vast majority of people tinctures are the preparation of choice for using herbs in most situations.

Now I am going to discuss the menstruum that I use to make tinctures. This is also going to require a bit of explanation as I do not follow the traditional method of determining the menstruum for making tinctures. Traditionally, tinctures were made using some percentage of alcohol and water. The percentage of alcohol used varied depending on the herb. These percentages have been recorded in various herbal pharmacopoeias. However, it is my experience that using these prescribed alcohol percentages is less than ideal. Firstly, these percentages were determined at a time when herbalism, alchemy, chemistry and reductionistic medicine had been in the process of diverging from their common roots. The reductionistic scientific model was beginning to coalesce into its current form. At that time, like today, some herbalists in the West practiced according to a more traditional, holistic model, others according to a more reductionistic model, and still others fell somewhere in between. The growing influence of the materialistic, reductionistic scientific paradigm led many to believe that the therapeutic actions of plants were due exclusively to their chemical constituents. In addition, those who subscribed to this model believed that the actions of medicinal herbs could be reduced primarily to the properties of a single constituent or a few chemically-related constituents. As a result, the recommended menstruum for macerating tinctures was determined by figuring out the best percentage of alcohol for extracting the single or a few related constituents that were believed to be responsible for the therapeutic actions of the plant. The recommended alcohol percentages for extracting individual herbs that are recorded in the various pharmacopoeias were derived in this way.

From the perspective of an holistic paradigm, the therapeutic actions of an herb are understood to be the result of synergistic interactions of all of its chemical constituents. As a result, using a particular alcohol percentage intended to produce the best extraction of an individual constituent is not ideal because that alcohol percentage might not work well or even be detrimental to the extraction of other chemical constituents. Therefore the ideal menstruum will be one that gets the best extraction of the largest number of the chemical constituents of the herb. Here's a somewhat extreme example of what that might look like. Myrrh resin (Commiphora myrrha) is usually extracted using a very high alcohol percentage, typically 80-100%. This is because many of the components of the resin are very poorly soluble in water but very soluble in high alcohol concentrations. However, myrrh also contains polysaccharides. Until the last couple of decades, polysaccharides were completely ignored by researchers because there were no known mechanisms by which they could be absorbed or have any systemic therapeutic action from the digestive tract. The conventional belief was that they are either broken down into their component sugar units, absorbed and used as fuel by our body, or they are "fibre" and just pass through the digestive tract without doing much of anything (except making it easier to have a bowel movement). In addition, reductionistic researchers were always looking for relatively unique, strong, drug-like constituents to explain the actions of medicinal herbs. This is partly due to their philosophical orientation, and also partly because much of the research was oriented towards finding chemicals that could be used as the basis for developing new drugs. Ubiquitous constituents like polysaccharides, organic acids and polyphenols were considered uninteresting. How could something that is found in most or all plants be important when considering the unique therapeutic actions of individual herbs? In fact, any herbs that weren't known to contain very strong constituents such as alkaloids, saponins or cardioactive glycosides were considered useless and their traditional use irrational. Researchers have fairly recently changed their tune on this one, but that was the conventional belief of the time. So, getting back to myrrh, no one would have considered polysaccharides important when determining an alcohol percentage to extract the resin. However, the polysaccharides are very important, particularly for the immune stimulating properties of myrrh. Unfortunately, polysaccharides aren't soluble in alcohol. In general, their solubility tends to start dropping off at around 20% alcohol and by 40% they are virtually insoluble. So they are more or less absent from myrrh resin tincture when it is extracted using very high alcohol percentages.

Another issue is that the alcohol percentages recorded in many of the pharmacopoeias for extracting individual herbs were usually developed by practitioners and researchers who used herbs as simples (single herbs). At present, most Western herbal traditions use herbs in formulations. This is problematic because when we mix different tinctures that are extracted using different alcohol percentages, the alcohol percentage of the mixture is going to be different than the alcohol percentages of the individual tinctures. This means that chemical constituents that don't extract well at the alcohol percentage of the mixture will precipitate out of solution to varying degrees and either deposit on the surface of the bottle or settle out in a less absorbable form.

In considering all of this, I came to the following conclusions:

  1. That I needed to determine the best menstruum for extracting the largest number of constituents of herbs; and,
  2. For the system of herbalism that I practice, in which herbs are almost always used in formulations, it is best to use the same menstruum for all of the tinctures that I prepare. That means that I am looking for a menstruum that will extract the largest number of constituents in all herbs, not just an individual herb that I am macerating at any given time.
After doing some research on the solubility of various constituents and experimenting with various concentrations of possible solvents, the menstruum that I finally settled on is 60% water, 30% alcohol and 10% glycerin for tinctures made from dried herbs, and 56% water, 33% alcohol and 11% glycerin for tinctures made from fresh herbs in order to compensate a bit for the water content of the fresh herbs. Since I make almost all of my tinctures from fresh herbs, it is the latter menstruum that I normally use. I have used this menstruum for all of my tinctures for the last ten years and found it to be superior to using alcohol alone and in different (and usually higher) concentrations for different herbs.

The beauty of this menstruum is that, although glycerin doesn't extract constituents that are highly alcohol soluble as well as alcohol, it seems to work better for these constituents when combined with alcohol as long as the alcohol is in a higher proportion. On the other hand, glycerin is very good at extracting constituents that that aren't very soluble in alcohol, like polysaccharides, and helps to stabilize them in solution. So the net result is that this menstruum extracts constituents that are very soluble in alcohol more like a 35-40% alcohol solution, whereas it extracts constituents that are poorly soluble in alcohol more like a 20-25% alcohol solution. One easy way to demonstrate this is to make two tinctures of marshmallow root (Althaea officinalis), one using 40% alcohol and the other using 30% alcohol and 10% glycerin. When we press these tinctures, the latter one will be much thicker and more mucilaginous. This is because the mucilage content of the herb is primarily made up of polysaccharides which extract much better in this menstruum.

Marshmallow (Althaea officinalis).

On the other hand, if I repeat this experiment and make two different macerations of a very aromatic plant that contains a significant amount of essential oil such as wild bergamot herb (Monarda fistulosa), or a plant that contains bitter alkaloids such as celandine (Chelidonium majus), I can not detect any noticeable difference between the aroma and flavour (except for the sweetness of the glycerin) of the two different versions of the tincture, indicating that the essential oil and alkaloid constituents are extracting at a similar level in both cases.

Wild bergamot (Monarda fistulosa).

This process of assessing the quality or identity of an herbal preparation on the basis of properties that are accessible to our physical senses, such as flavour, aroma, appearance, etc., is called organoleptic analysis. Our senses, when suitably trained, are incredibly adapted to this kind of analysis, as in the case of people who can detect the subtleties of a fine wine. The same applies to herbal tinctures. To me, the ultimate test of the quality of a tincture is how closely its flavour and aroma resemble that of the fresh, living herb.

The final issue with regard to the menstruum that I use is that some people might argue that, even if this menstruum can extract constituents the are highly soluble in alcohol similar to a 40% alcohol solution, that is not enough alcohol to extract them efficiently. However, most herbal constituents are somewhere in the middle with regard to their degree of water and alcohol solubility and extract in the equivalent of a 30-40% alcohol solution very well. In addition, constituents that extract best in a high alcohol solution, like monoterpenes, alkaloids and resins, extract fairly well in this menstruum and are also very potent constituents that still have a strong therapeutic action even in a slightly lower concentration than is obtainable using higher alcohol concentrations. The fact that I am preparing 1:5 fresh herb tinctures is also a factor. They will dissolve in a 1:5 maceration better than a 1:2 or 1:1 maceration because there is more menstruum for them to dissolve into in a 1:5 extraction. It is also doubtful that our body can absorb these constituents efficiently in higher concentrations anyway. Since my goal is to create tinctures in which the constituents are in a similar proportion relative to each other as in the living herb, using this menstruum makes more sense. I am not extracting an essential oil, I am extracting an herb!

Another consideration is whether or not we might get an even better extraction if we maintain the alcohol at 30% and increase the amount of glycerin. This might be a bit better for some constituents, however, from my experience it seems to be important that the alcohol percentage is a fair bit higher than that of glycerin. In addition, I find that using more than 10% glycerin makes the tincture too sweet and many people find higher concentrations of glycerin somewhat irritating in their throat. Although the slight sweetness of this menstruum is useful in terms of making some herbs more palatable, if it's too sweet it masks the flavour of the herbs too much. Some of the therapeutic properties of herbs are enhanced by tasting the herb, presumably by reflex actions from the taste receptors in our mouth. For instance, there are many therapeutic properties that are related to the bitterness of an herb. Tinctures that contain more than 10% glycerin mask the bitterness too much and reduce the effectiveness of these properties.

The last point on glycerin is that we always use food grade vegetable glycerin. There is lower grade glycerin that is used for other purposes, but it is not suitable for making tinctures.

OK, so now we've made it through another long explanation and we can finally get back to our blue vervain herb that is chopped up sitting in our jar. To summarize, the herb is in a 950 ml amber round packer that will actually hold 990 ml when filled to the appropriate level. It has a polypropylene lid with a loose low density polyethylene liner. Now we want to fill up the jar with our menstruum, which contains 56% water, 33% alcohol and 11% glycerin. We want to minimize the amount of air space in the jar once it is filled because the more air that is present, the more oxidation that will occur while the herbs are macerating. However, we must have some air inside because we need to be able to shake the maceration to help the constituents dissolve. This only works if there is a bit of air inside because it is the movement of the air bubble that shakes up the contents of the jar. I have found that the maximum amount that we can fill the jar and still allow the contents to be shaken efficiently is about 1/2 cm (3/16 inch) from the top. Once we fill the jar to 1/2 cm from the top, the lid must be screwed on tight enough that it doesn't leak, but not so tight that we split the lid (which is possible with plastic lids if we get over zealous).

It is important to rinse the outside of the jar once it is sealed so that there is no residue from the plant juices or glycerin (from the menstruum). Otherwise it is possible that mold will grow on the jar while it is macerating.

The final thing we need to do is put a label on the jar. I store my macerations in boxes, so I put the label on the lid. It needs to contain the following information:

  1. The name of the herb and part used.
  2. The concentration of the maceration.
  3. Whether its a fresh or dried herb extraction.
  4. The date it was made.
For the blue vervain tincture that I made I wrote the following on the label:

Verbena hastata herb
1:5 Fresh
July 1, 2012

Now that our maceration is sealed and labeled, it is necessary to shake it regularly for awhile. This helps to get the constituents into solution and to break up the plant tissues a bit as they soak and soften, which facilitates the release of the constituents from the plant. I usually shake a new maceration vigorously for about 20-30 seconds twice a day for the first week, then once a day for another week or two. After that I shake them once or twice a year until I am ready to press them. Once I've decided to press a maceration to make the tincture, I will shake the jar once a day for a week immediately prior to pressing it.

The last little complication in this process is that plant tissues contain air spaces. Some more than others. As the plant material is soaking, the air spaces in the macerating herb will gradually fill with menstruum. This process takes a week or two and the shaking of the maceration helps to facilitate this process. Once the plant tissues are fully saturated with our menstruum, the size of the air space in our bottle will have grown. At about the two week point, just before I stop shaking the jars regularly, I will open them and top them up with additional menstruum back to 1/2 cm below the top. When we do this, it is important that we carefully clean the outer rim of the jar and the inner surface of the lid that comes in contact with the rim. A very small piece of paper towel or a section of toilet paper works well for this. There are two reasons why this is necessary. These surfaces will get coated with tincture and bits of plant material. If we don't clean it, the lid might not seal properly when we screw it back on. Also, if there is any tincture present on the rim, once the alcohol evaporates the remaining residue is a suitable medium on which mold can grow. Mold can't grow right into the tincture, but if it is on the rim it could contaminate our tincture when we pour the maceration out of the jar when it is finished.

Herbal macerations need to be stored in the dark at all times. I store mine in boxes with dividers. When I don't have boxes with dividers I make the dividers.

I have found that the ideal amount of time to macerate tinctures is three months or more. The absolute minimum amount of time is one month, but three months is preferable. Prior to three months the macerating herbs haven't had the opportunity to soften enough to be able to efficiently extract their constituents. After three months most of the constituents of the herb are either in solution or extractable when we press it because the macerating herb material will have softened sufficiently. Additional time macerating will only slightly increase the potency of the tincture. That being said, we don't want to press a tincture until we are ready to use it. As I've stated earlier, the greatest amount of degradation of the constituents of an herb occurs once the tincture is pressed. So it is best not to press a tincture until we need it and to macerate it in quantities that we will be able to completely use within three to six months of pressing it.

One of the great things about macerating herbs is that as long as we prepare our herbs and maceration in a conscientious way to maximize the quality and potency of our tincture, and the macerations are sealed well, stored in the dark and not opened, macerating tinctures will maintain their quality and potency for a very long time. I have tinctures that macerated for 10 years or more before I pressed them and they are just as good as those that were pressed within a few months. The one exception to this is herbs with a lot of aromatic sulfur-containing compounds, such as those from the Onion (Alliaceae) and Mustard (Brassicaceae) families. These kinds of constituents tend to be less stable in solution. It is best to press tinctures of herbs from these families within a year or two and use them within three to four months once they are pressed.

This is the end of Part 3 of this series. In Part 4 I'll discuss the different kinds of equipment that are available for pressing and filtering the maceration.


Sunday, July 15, 2012

Making Medicine, Part 2 of 5: Preparing Blue Vervain to Make a Tincture

This is the second in a series of five posts in which I am using the process of wild harvesting and making a fresh herb tincture of blue vervain (Verbena hastata) as an example to explain in detail the process of making medicine. Part 1 in this series was posted on July 9th.

In my practice I primarily use tinctures made from fresh herbs, so the next step is to use the blue vervain that we harvested to make a tincture. When you make as much tinctures as I do, you appreciate good equipment. I have experimented with a variety of tools over the years and will discuss some of them here. I am also going to use the process of preparing blue vervain tincture as an example to explain some of the important details regarding making tinctures.

The basic idea is that we want to separate the more potent from the less potent parts of the portion of the plant that we harvested, chop it up and put it in a bottle with the appropriate menstruum (pronounced MEN-strew-um: the liquid that we use to absorb and preserve the constituents of the herb). As an herbalist, it is important to me that the way I prepare a tincture is consistent so that I know that the tincture of any particular herb that I make from year to year is very similar in potency. There are factors that affect the potency of the herb, like weather conditions, that I can't control. However, if the weather conditions are particularly incompatible with the requirements of a particular herb in a particular year, I won't harvest that herb. What I can control is how I prepare the tincture. In order to accomplish this, the portion of the plant that I use needs to be consistent as must the amount of herb that I use for any given volume of menstruum.

When using fresh herbs, I recommend a 1:5 potency. This means that 1 g of herb is used for every 5 ml of menstruum. There are herbalists who recommend a higher potency for various reasons. However, I disagree with using a higher potency than 1:5 for fresh herb tinctures. I will do a detailed post explaining why I prepare tinctures the way I do at some point in the future, but the bottom line is that 1:5 fresh herb tinctures work and a higher potency isn't necessary. Also, the greater the potency that we use above 1:5, the greater the amount of herb we end up using in order to get the same results. For reasons related to the chemical characteristics of the constituents of an herb, using twice as much herb doesn't make a tincture that is twice as strong therapeutically. For example, a 1:2.5 potency tincture should be twice as strong as a 1:5 tincture because we are adding the same amount of herb to half as much menstruum (2.5 ml instead of 5 ml). If this were true, then when we use a 1:2.5 tincture we should get the same results using a dosage that is half as much as the dosage we use for a 1:5 tincture. However, it doesn't work out that way. We need to use more than half as much of a 1:2.5 tincture to get the same results. This is because as we add more herb to the same volume of menstruum, at some point the percentage of constituents that actually dissolves in the menstruum starts to drop off. In addition, for most herbs it is physically impossible to get enough herb into a given volume of menstruum above a 1:5 or 1:4 potency. This necessitates methodologies such as grinding the herbs, percolation or macerating tinctures more than once, which are more time and energy intensive, often require the use of expensive equipment, and lead to a greater level of degradation of the constituents of the herb. Therefore higher potencies are unnecessary and wasteful. For home use, you don't need to be as accurate with your measurements as I am recommending here, but the more accurate the better.

The equipment I use for preparing fresh blue vervain tincture.

In preparing a tincture we need to be able to measure the amount of herb that we put into each bottle. For this I use a triple beam balance, but digital scales will do as long as they are calibrated to 1 g increments or smaller. We also need to know how much herb to use per bottle. Traditionally the way we calculate this is to first measure how much fluid the bottles we are using contain when they are filled to 0.5 cm (1/4 inch) from the top. It is necessary to measure this because the volume indicated for the bottle is usually not based on filling it this close to the top. Beakers and measuring cups are not accurate enough for this. It is necessary to use something that is calibrated in 1 ml increments. This usually necessitates the use of a graduated cylinder.

Once we have an accurate read on how much fluid our bottles contain, to approximate how much herb we will need for a 1:5 tincture we divide the total by 6, that is for 1 part herb plus 5 parts menstruum. This is not 100% accurate because herbs are usually less dense than water and not all herbs are of equal density. However, although this is an approximation, it is surprisingly accurate. It is sufficient for most situations. The key is to get as accurate a measurement as possible of the volume of the bottles we are using. I have done extremely detailed calculations for all of the tinctures that I make and, with only a couple of exceptions, this approximation is accurate to within 1-2%, which is good enough.

The harvested portion of one plant.

Once we know how much herb we need per bottle, it is necessary to separate the usable from non-usable parts of the portion of the herb that we harvested. When harvesting the aerial parts of plants (the parts that grow above the ground), this usually means that a portion of the stalk isn't used. This is because the primary purpose of the stalk is to hold up the leaves and flowers. As a result, the stalk tends to contain mostly dense fibrous tissue and a much lower proportion of the therapeutically active constituents. The amount of stalk that has to be removed can be anywhere from 0-100%, depending on the plant and the portion of the plant that is harvested. For most plants from which we harvest the aerial parts we harvest the terminal 25-40%  of the plant and remove 80-90% of the primary stalk and 60-75% of any well-developed secondary stalks. The specifics depend on the species of plant and at what stage we are harvesting it. The portion of the stalk that is usable tends to be the new growth that is less stiff and more succulent. To determine the usable portion for a particular species, we start at the lowest part of the stalk, cut off a small section and taste it. Then cut a similar sized section about 20% further up the stalk, then at 40%, 60%, 80%, and finally the top portion. Finally, we taste a piece of a leaf. The point on the stalk where the flavour of the stalk is about 2/3 to 3/4 as strong as the flavour of the leaf is the point at which the potency of the stalk is strong enough to use. We remove all of the stalk below that point and use all of the stalk above that point. The reason that the taste of the stalk can be used to determine its potency is because its flavour corresponds to the concentration of many of its active chemical constituents. For plants that are relatively bland in flavour because they have little to no aromatic, bitter or pungent constituents, there isn't much difference in the flavour of the different aerial parts of the plant. Therefore we just use the portion of stalk that is less stiff and more succulent.

Blue vervain is unusual in that the flavour of the entire stalk is pretty strong. This is because its flavour is primarily due to chemical constituents called iridoids and the iridoids are in a fairly high concentration in all of the aerial parts of the plant. Nevertheless, for the most part I still only use the less stiff and more succulent parts of the stalk. Overall I remove a little bit less stalk than is typical for most herbs. However, with this herb, if the amount that I harvested is a bit short, I can just use a bit more stalk rather than having to harvest more plants.

The part that is used (above) and the amount of stalk that is not used (below).
This is the same plant that was shown in the previous picture

The next step is removing the unused stalk from all of the plants that we harvested. This can be done with a knife or scissors, but since we tend to cut the stalk at the point where it becomes softer and less fibrous, for most herbs the stalks can be easily torn with our fingers, which takes less time. Once we've separated all of the usable portions of the plants that we harvested, we need to weigh them to make sure that we put the right amount in each bottle. I use four standard sizes of bottles. The blue vervain that I harvested was intended to prepare the largest size, which is a 950 ml bottle. However, the volume of bottles that are narrower at the top than the full width of the bottle are usually calculated to about the top of the shoulder. When the bottles I use are filled to 0.5 cm from the top, they actually hold 990 ml. To determine how much of the usable portion of the herb that we need to use for a bottle this size, we divide 990 by 6 (for a 1:5 tincture), which is 165 g. Although our proportions are made up of 1 part herb, which is measured in grams, and 5 parts menstruum, which is measured in millilitres, this conversion works because the density of menstruum is almost the same as for water. The density of water is 1 g/ml, so 5 ml of water is the same as 5 g of water.

The amount of herb material that is used to prepare one bottle
(990 ml) of tincture with the removed stalks below.

When I am harvesting any herb, it is important for me to determine in advance how much that I am going to need. That means the number and size of the bottles of tincture that I need to prepare, how much of the usable portion of the herb I need per bottle, and approximately how much extra that I need to harvest to account for the unused portion of the plant. I don't want to be short or I might have to go out again to harvest the same herb. In some cases, due to the number of herbs that I need to harvest, weather conditions, etc., harvesting an herb a second time might not be possible. So I might run short before I am able to prepare it again the following year. The flip side is that I don't want to over-harvest because it is wasteful and disrespectful to the medicine. When I'm out harvesting I bring a small spring scale that is accurate to within 10 g, so I can make sure I harvest the right amount. I will always harvest just a bit more than I need so that I don't accidentally run short. Any small amounts of extra herb I dry and use for teas.

After I processed 165 g of the usable portion of the blue vervain to make my bottle of tincture, the amount of stalk that I had removed was 51 g. That means that I had to harvest an extra 31% of the herb to get the amount that I needed. If I had harvested the blue vervain a bit later, the proportion of unused stalk would have increased because as the plants mature the stalk gets stiffer and the amount of stalk between the nodes (the points where the leaves join the stem) gets longer.

Once we have measured the appropriate amount of the usable parts of an herb, we need to chop it up. For this we need a fairly large hardwood cutting board and some kind of knife. Over the years I have experimented with just about every kind of knife for chopping the many herbs that I use. Some herbs are best chopped using a cleaver, a few require a serrated knife, but for most herbs the best knife by far is the mezzaluna. This is a curved knife with a handle at each end (see the first photograph in this post). When used correctly, it can finely chop herbs much more quickly than other knives. This is important because the process of chopping our herbs requires finding a balance between two opposing requirements. On the one hand, the more finely we chop the herb, the greater the surface area that we create that allows its constituents to dissolve in our menstruum. On the other hand, the more finely chopped our herb and the longer it takes to do it, the more it is exposed to air which results in greater oxidation of its chemical constituents. Most constituents are less potent when oxidized and in some cases it may even change their properties. It is true that a few constituents are more potent when oxidized, but this is not the case for the vast majority of them. In addition, they will have plenty of opportunity to oxidize after we press the herb, the final stage in making a tincture. For the best results, we want to minimize the amount of oxidation that takes place before and while the herbs are macerating. Maceration is the process of soaking the herbs in our menstruum. With the mezzaluna, I can chop an herb a little bit finer than I would with other kinds of knives in about half the time. It doesn't get any better than that! I really love those special tools that significantly increase the efficiency of the work that I do. The mezzaluna is one of those special tools. In choosing a mezzaluna, it is important that it be a larger one, 25-30 cm (10-12 inches) wide. Do not skimp on quality. Purchase one that is professional quality. The best ones are made in Italy or Portugal using high quality molybdenum vanadium steel. The ones made in China are not good. Also, only use the ones that have a single blade. One of my students once bought one with a double blade. She though this would make it easier. All it did was slow things down because the herbs kept getting caught between the blades. I don't believe they even make double bladed models in Europe.

Using a mezzaluna takes a bit of practice. Basically we hold the handles and rotate the blade back and forth over the herbs. Each time we do that we twist the blade to change the angle very slightly, first one way and then the opposite way on the next stroke. This allows it to move forward across the cutting board. What works best is to cut moving forward down the board, then begin at one of the front corners and cut diagonally in one direction, then cut diagonally in the other direction from the other front corner. Keep rotating between cutting in these three directions until the herb is chopped the right amount. It is very important that the cutting board is oriented so that the grain of the wood is running down the board away from us. Never use a mezzaluna to cut parallel to the grain of the board. This is because when we slightly twist the blade at the end of each stroke, if we are cutting with the blade parallel to the grain, it digs between the layers of wood. Over time it will start cutting out thin slivers of wood which will significantly reduce the life of the cutting board.

This is the what the herb should look like when it is sufficiently chopped.

This is the end of Part 2 of this series. In Part 3 I'll discuss making a blue vervain maceration.