wow, has it really been 3 years since i did an instructable?! amazing.. work and adulthood get in the way i suppose...well, almost a month ago i got notice that there was a bacon related contest.. and i had to be a part of it.. so heres my entry!
but i'm an engineer.. i cant cook anything that cant microwave.. and i figured i would share some fun with chemistry in making some homemade caffeinated bacon soap from scratch in your kitchen, if your brave..
Disclaimer: this instructable involves caustic chemicals.. multiple forms of drain cleaner.. and bacon.. due care should be taken to work in a well ventilated area, using rubber gloves and *goggles*.. the right kind, with splash resistant vents... in the case of working with strong acids or bases always have a plan to neutralize the spill.
don't fuck around and you'll be fine
Step 1: Caffine
first we'll need some caffeine, and while you can buy it commercially as a pure powder for additives.. i think its cheating.. and its also probably a wildly dangerous temptation to keep just hanging around the kitchen.. so we'll need a source of caffeine, I'll be using the some off the shelf tea.. whatever is cheapest will work.. it really doesn't matter, we're only going to be taking the caffeine.
oh yeah, did i mention caffeine is in fact poisonous in high concentrations.. don't get any dumb ideas like licking the spoon, or spicing up your coffee.. you'll probably die.. and i will feel guilty.. and i don't want to feel guilty..
If your going to buy caffeine or if your planning on making the soap in bulk, its cheap..http://www.google.com/search?q=pure+anhydrous+caffeine
but in the next step i will show you how to extract it yourself. if you're going to buy caffeine, or if you don't want caffeinated soap.. skip to step 3.
Step 2: Acid-base Extraction
some stuff you'll need:an acid (vinegar or sulfuric acid from drain cleaner)
pure sodium hydroxide from drain cleaner
methylene chloride aka dichloromethane, this can be purchases from art supply stores as "attack epoxy remover"
I'm going to be somewhat brief here, i originally extracted caffeine for fun as a project months back and had intended to use the photos taken from that event to write this article. Unfortunately i found that i didn't photograph any of it.. and so i started making more caffein for documentation purposes.. but one chemical i needed for this i was unable to source on a saturday and without enough caffeine to conduct a solubility test my substitution failed and i lost almost the entire yield.. so.. *READ* because the pictures will differ from reality slightly..
Get yourself a pair of scissors and start cutting open your packets of tea and dumping them into a large *glass* bottle or jug go ahead and use up the whole box, we can figure out the dosage we're trying to add to the soap later, but at least here you can get some idea of how much caffeine we're working with unlike working with a powder since we've had tea and have some idea of the effects of a bag of tea.
Once you have the tea your going to use you'll have to dump this into a glass pot and cover with a decent quantity of water. You'll need an acid to begin the process and in my kitchen i will be using an eyedropper full of sulfuric acid (H2S04) i obtained from ace hardware and using PH strips to keep an eye on things. if your going to go this route be sure not to use any aluminum implements when working with the acid. steal,glass, wood or plastic will survive.. You may be fearful of using sulfuric acid.. you can substitute acetic acid (distilled white vinegar) but since its pretty dilute, you'll need to add less water to your pot so you'll have less to boil off later.
we'll pour off the acidic tea into another glass container and add more water to the tealeaves to wash them again, again making the solution acidic.. you might want to repeat one more time just to make sure we've dissolved as much caffeine as we can.. once thats done we'll need to boil this all down to a volume that will reasonable fit into my sep-funnel.
now that our solution is boiled down to a small enough volume we'll let it cool down a bit to about 120F and go off and make a strong lye solution to finish off our extraction.. to do this measure out a few table spoons (your not using aluminum are you?) of the lye (sodium hydroxide) and dump them into a glass containing enough water to dissolve all the lye, if you need to, add more water.
when all of the lye is dissolved start pouring the lye solution into your tea lowering the acidic ph into being very "basic", you'll know you have it right when your tea turns almost black and inky in texture once it has *stop* adding lye.. more lye will just reduce our yield.
using a funnel pour the foul black/brown smelly mess into your separatory funnel (or a large glass bottle/jar that can easily contain it)
pour in a layer of our other nasty chemical "dichloromethane" (your well ventilated right?)there should be a good visible layer ~1/2 inch thick added to the bottle.. the dichloromethane will sink to the bottom forming its own layer.. a bit like salad dressing.. they don't mix (immiscible) but we're going to put the lid on and give it a couple good shakes, then take the lid off (pointing the top away from you) to let the gas vent.. glass makes a terrible pressure vessel.
let the layers separate out again and discard the dark liquid layer (this is much easier if your using a sep funnel).. let the dichloromethane evaporate outside and recover the crystals of caffeine later by scraping the evaporating dish clean.
you now have pure caffeine!
Step 3: Bacon..
in this next step, your going to have to eat a lot of bacon... go ahead... i'l wait for you.. come back when you have ~100mL of delicious bacon grease.. fried.. microwaved.. whatever... all grease is good..
Step 4: Filter
So first things first, we'll have to reheat our bacon grease to about 150 degrees (or until its mostly golden-clear) and pour this through a coffee filter, you'll have to keep swapping them out depeding on how much crap is in your bacon.. but its worth it.. i dont know about you but i dont want actual bacon bits in my soap.
Step 5: Saponification
ahh the punchline of soap making...
first to prepare we'll need to mixup another lye solution using a very specific quantity of lye.. i will spare you the specifics of cold-process soap making technique and just tell you the "saponification number" is a ratio of base to our fat.. for "lard" aka pig fat that number is ".141". since i'm using a gram scale i measure the rough density of our bacon grease to be about 1g/mL (close enough anyway) so for my batch of 125mL of bacon grease i'll be adding (125*.141) = 17.6g's of lye needs to be added in water.
so again i dissolve the lye in the *minimum amount* of water required and wait for the solution (which is pretty damn hot) to cool down to ~120F
ok, so at this point both our bacon grease and our lye water should be at about the same 110-130 degree range if not.. heat or cool as necessary..
slowly pour in the lye water solution into the bacon fat while stirring well until everything is in, then stir stir some more, eventually the mixture will become uniform and milky and slowly thicken up and eventually get to a stage called "trace".. this is where drops from the mixing spoon when dripped onto the surface does not flatten out quickly.. when making this batch of soap this took something like 1.5 hours.. so.. keep warm and keep stirring..
Step 6: Seasoning!
now that things are nice and thick i mix up our caffeine from the previous step by dissolving it in a small quantity of water, you could probably add it in powder form here but i wanted to make sure it all dissolved and there were no crystals.
then i added a spoonful of fresh cracked black pepper (i'm a friggin gourmet!) and mixed it well, i let things firm up a bit more before moving on to molds.
Step 7: Molding
ok, what can i say here.. i didn't have time to make bacon molds ;) so i'm just going to use two cups to make simple round bars.
once you pour your now yogurt like soap into the molds put them away and check on it after the first 24 hours to make sure the soap has firmed up and isn't runny and should have any voids full of clear liquid (lye!) .. but otherwise ignore it for 3 weeks and its ready to use!
Step 8: Oh God What Have I Done.
how good is the soap?:
i don't know, the soap is still curing, and it wont finish before the contest deadline.. but i imagine you will smell like pork.. though.. its not as porky as one might think.. right now it smells like peppery bacon with the pepper winning out a bit..
(edit: it turns out this makes pretty reasonable soap.. the pork scent has died down into something that isnt very strong and after washing with it, my hands do not smell like pork at all)
how much caffeine should i put in?:
truth be told.. i don't know..it doesn't matter.. the MSDS sheet for caffeine sadly tells me that absorption of caffeine through the skin is unlikely.. and minimal at best.. on the other hand i have had friends swear by it.. if you really want you can just match the commercial caffeinated soaps if you really want.
damn this instructable is sloppy:
sorry.. i've only got a couple hours!!