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making extract with a soxhlet apparatus

ive seen several people talking about making pepper extract, so i thought id share how i go about it.

here's the soxhlet apparatus. it consists of a soxhlet, the bit in the middle. a condenser, the bit on the top. and the flask, the bit on the bottom.
here is what happens, once the flask is heated vapors travel up through the soxhlets sidearm up into the condenser, which condenses the vapors back into a liquid wherein they fall back into the soxhlet. the soxhlet is designed such that it will fill up with solvent and then drain itself almost completely back into the flask. it accomplishes this by starting a siphon once it begins to overflow through the small u shaped siphon tube you see on the side, this siphon will not break until it sucks air so naturally it empties almost completely. this process will cycle pretty much indefinitely as long as you provide heat and cool water to the condensor.

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heres the pepper we are extracting, dried bih jolokia pods, i have hundreds of them, id probably have more if the plant didnt catch a virus :eek: or atleast what i think was a virus.

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anyway, i tossed a bunch of these into a blender untill they were reduced to flakes

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these flakes were packed into a glass thimble, which is basically a container with frited glass disk on the bottom that allows solvent to drain through. you absolutly do not need a thimble, alot of people just stuff a bit of loose cotton or glass wool into the base of the siphon tube. keep in mind tho that w/e you are extracting will float, so you need to get a plug of cotton on top of w/e you are extracting so that it will not float around

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and now we fill the flask... with 200ml of n hexane, good and cheep non polar solvent. we use hexane because its non polar, a non polar substance is not misicible into water hence it will not extract water soluble stuff like chlorophyll and w/e else is is in plant tissue. im not the person to teach you why things are polar and why things are not, but i can tell you that it has to do with molecules dipole moment.


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and now we apply heat! hexane boils quickly, at 70c. notice those little black bits on the bottom? those are boiling chips, i use them to get nice even safe boils. theres a phenomenon called "bumping" wherein you heat a liquid past its boiling point and it explosivly boils over at some trigger... like a bump. if you are lucky you just get a boil over into your distillate, if you are unlucky you get burned. you see 'bump flasks' on some apparatuses to stop contain this.

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soxhlet filling up...

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almost full...

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to many photos!
 
An old neighbor of mine had a very similar rig and did "essential oils" (rose, rosemary, sage, a few others) with it. It's quite a process!

Thanks for sharing these pics - fascinating! That end result looks really dangerous!
 
Denatured ethanol usually contains methanol, which is poisonous. Don't be tempted to drink anything containing denatured ethanol. It will mess you up. Vodka or another high alcohol content liquor should be ok. Essential oils are usually extracted by steam distillation. This will only work if your natural product is volatile (meaning low boiling). The capsaicinoids are relatively high boiling so the steam distillation method probably won't work too well for extracting them from peppers. I will look up some research papers over the next couple of weeks and try to find a safer method.
 
Denatured ethanol usually contains methanol, which is poisonous. Don't be tempted to drink anything containing denatured ethanol. It will mess you up. Vodka or another high alcohol content liquor should be ok. Essential oils are usually extracted by steam distillation. This will only work if your natural product is volatile (meaning low boiling). The capsaicinoids are relatively high boiling so the steam distillation method probably won't work too well for extracting them from peppers. I will look up some research papers over the next couple of weeks and try to find a safer method.

Yeah - that validates what my neighbor said about making rose oil. But he also made hash oil which used something more volatile than steam - not sure uf it was ethanol or something else...the whole thing looked really unsafe but he was very cautious - always wore protective eye gear, gloves, heavy apron & kept a fire extinguisher near at all times. It was a similar rig but not exactly the same.

It's all pretty amazing - I used to see "essential oil: rose" and think "that's just ridiculously expensive!!". - then after seeing how much flower material was required and how involved the extraction process my whole attitude towards it changed.

Must take a hell of a lot of peppers to get a vial of extract!
 
Denatured ethanol also contains denatonium benzoate - the denaturant, which causes the liquid to become un-drinkable. If you were to try it, you would become violently ill - it's kind of like ipecac. It is so chemically bonded to the ethanol that you cannot distill it or separate it and make it safe. An idiot chemist I used to work with thought he could filter it through charcoal and make it safe to drink because he was sooo smart. He passed out "samples" at a company event. Everyone that tried it got sick. Friggin' over educated idiot.
 
Folks, the denatonium is added as an extremely bitter tasting principle to give the denatured alcohol an unpleasant taste. Its addition can be thought of as a safety measure, so that someone who might accidentally drink it ( like a kid) would stop doing so. Denatonium is added to antifreeze (ethylene glycol, which is a poison) and other solvents that look like water but can cause harm for the same reason.

Visual indicators such as dyes and stinky odor chemicals are also added for the same purpose, which is to let people know that the ethanol has been denatured. The substance used to denature alcohol is most often methanol, but other organic solvents are sometimes used. Denatonium is sometimes used alone to denature alcohol but often it is used in combination with methanol. The reason that methanol is still used it that it is not easy to separate from the ethanol. Denatonium is not chemically bonded to ethanol. It is simply a solution and is quite easy to separate from ethanol but you need to know what you're doing.

The wiki article on this is reasonably accurate: http://en.wikipedia.org/wiki/Denatured_alcohol
 
Very nice set up!!!! I have used alcohol (151 proof or better) in a coldfinger extractor and it did a great job as well. Capsaicin has a boiling point (210*-220) and alcohol has a boiling point of 172* so it works out quite well. unfortunatly I don't have pictures of mine (and it's still packed away) but it is based off this unit that is made by Eden Labs:

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It is placed in a pot with a false (raised) bottom full of water and then heated. The tubes comming out of the top are to keep ICE water circulating, the 1 out the side of the jar is for a themometer and can also be used to let the alcohol vapors out to condense the extract....
 
There is a problem with units in the original cold finger apparatus post.

The boiling point of ethanol is 78 deg C (172 deg F).
The boiling point of capsaicin is 210-220 deg C (410-428 deg F).
The boiling point of water is 100 deg C (212 deg F)

This is another apparatus for extracting organic compounds from solid samples using volatile organic solvents. The sample to be extracted i.e. dried pods or whatever, is placed in a little cup above the ethanol. Heated by boiling water, ethanol boils, the vapour condenses on the cold finger and drips through the sample back into the ethanol in the bottom of the flask. So long as there is no pressure build up in the apparatus, it looks reasonably safe to use. I think that you mean "concentrate the extract" at the end of your last post. The extract is left at the bottom of the flask once the ethanol is boiled off, right?
 
im sure you could get something out of it.
problem is that isopropanol is pretty polar, like ethanol right? you are going to get water soluble plant junk with your resin.

i havent done it, but i read about a 2 stage acetone extraction in that book "capsicum the genus capsicum". ill have to look into that again some day.
 
hmmm, i wonder if said acetone extraction would work with the isopropyl alcohol... it's less polar than ethanol and acetone. I just found this link

I don't mind plant junk if I'm eating it anyway, i just want to make a basic extract of the good stuff :D could i let it sit for a few days in a glass jar with intermittent shaking, then filter the alcohol and let it naturally boil off outside then collect the residue?
 
you could. but i wouldn't bother waiting for days. even at room temp... id just wait a few hours.

i think you will find the yield to be less than satisfactory at mason jar scales tho. until you scale up to like an lb or so of dried pods at a time you are likely only harvesting single digit grams.
 
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