Posted Mon Jul 9, 2012, 10:11am Subject: Re: Weird things I've done lately with coffee:
DavidG Said:
I want to try this too! We have a drink blender (Magic Bullet) for smoothies and such that should do nicely. And, I have the SS coava disk for my aeropress. The first thing I thought of for an aromatic emulsion of coffee would be to spread it on things for breakfast! I am sure more creative minds can think of other food uses.
Another idea that occurs is that it might make marvelous flavoring for ice cream... or dressings... or [sky's the limit].
Netphilosopher, keep up the coffee mad scientist exploration! We dilettantes will try to follow along.
Keep in mind - it's not a THICK emulsion. You can't spread it. It's definitely thicker than normal coffee, but by no means does it have any "stick".
I should have snapped some pictures.
By emulsion, I mean that the liquid is comprised of dissolved solids, and fully suspended solids entrained with fats and oils (which is normally not miscible with water), which are broken into teeny droplets and dispersed throughout the brew water. Usually, an emulsion is separable by settling or centrifuging.
Think of a vinegar and oil dressing - when you combine the two, they are separate liquids. Blend it and it becomes a homogeneous mixture that appears opaque. Let it sit for a while and the oil will gradually separate - or you can run the dressing in a centrifuge and they will separate.
The magic of food science is you can add an ingredient (like a bit of mustard) which is an emulsifiER - it promotes keeping the blended liquid in suspension. So much so that even centrifuging some storebought vinegar and oil dressings won't separate the two components.
Mayo is also an emulsion. It is a combo of oil, an acid (either vinegar or lemon juice), and egg whites. In this case, the egg whites contain lecithin, which is a very effective emulsifiER - keeping the vinegar and oil "mixed".
Most of the time, when immiscible (non mixable) liquids are forced to be combined, they appear cloudy or opaque. Note the term "immiscible", which is different than "dissolved".
So, not only does coffee consist of dissolved solids, apparently there must be enough of an emlusifier in ground or blended coffee beans which is acting to keep the lipids (fats and oils) in suspension. Furthermore, these bits of emulsified fats can also keep small particles of coffee grounds in suspension - small enough they pass through a paper filter, but large enough to clog a 0.02 micron syringe filter.
I guess what surprised me was the completeness that this remained as this tan-colored opaque liquid - I expected to run this through a filter and have normally clarified coffee.
I do wonder what would happen if I dry some of it and re-constitute it?
------------------------------------------ ----------------------------------------- Le café doit être noir comme le diable, chaud comme l'enfer, pur comme un ange, et doux comme l'amour.
"There is no right answer with coffee. There is only the elixir in your cup at the moment you partake."
"...I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind;..." - Lord Kelvin RECIPES thread => http://www.coffeegeek.com/forums/coffee/machines/585708
calblacksmith Moderator Joined: 25 Nov 2007 Posts: 5,761 Location: Riverside, Ca, U.S.A. Expertise: I live coffee
Espresso: ECM Veneziano A1 Grinder: Many different commercial Vac Pot: 40s era Silex Drip: Milita, Bunn&Curtis... Roaster: Cast iron pan, gas burner
Posted Tue Jul 10, 2012, 9:21pm Subject: Re: Weird things I've done lately with coffee:
I brewed espresso with ah one time by accident. for me, nasty taste that I could not spit out fast enough, burned my mouth for hours. Not a thing I want to try again. Good luck with that.
OH, BTW it really depends on what you are using it for but water is nearly the universal solvent, at least that is what the chem people I know say YMMV!
In real life, my name is Wayne P.
Feed the newbs, starve the trolls and above all enjoy what you drink!
Nah, it's a decades-old "braun" 525 watt blender. Nothing special.
------------------------------------------ ----------------------------------------- Le café doit être noir comme le diable, chaud comme l'enfer, pur comme un ange, et doux comme l'amour.
"There is no right answer with coffee. There is only the elixir in your cup at the moment you partake."
"...I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind;..." - Lord Kelvin RECIPES thread => http://www.coffeegeek.com/forums/coffee/machines/585708
666madmonk Senior Member Joined: 22 Feb 2012 Posts: 5 Location: Washington State Expertise: I love coffee
Posted Fri Aug 17, 2012, 11:28am Subject: Re: Weird things I've done lately with coffee:
This is a very interesting thread! I am inclined along "mad scientist" lines myself; I'd like to try some of these experiments and see how they turn out for me. Has anyone tried making a cofee liqueur by doing an etanol extraction, then adding some strong water-extracted (espresso) and diluting and sweetening the end product?
trickydicky Senior Member Joined: 18 Jul 2012 Posts: 6 Location: Australia Expertise: I love coffee
Posted Sat Aug 18, 2012, 6:39pm Subject: Re: Weird things I've done lately with coffee:
Netphilosopher Said:
#2 - the emulsification trial:
Wonderful cup of coffee that his reminiscent of cafe au lait with an overlay of gently roasted coffee grounds. Aroma was quite fascinating - that's just with Eight o Clock Colombia. I will be trying it again at some point with a Uganda, Ethiopia or some other of the African varietals.
I still have a sample of it - after a week it remains emulsified. The only thing that's been successful at separating SOME of it is adding 2ml of the coffee emulsification to 2ml of ethanol (75.5%), agitating, then adding 2ml of distilled water after 3 minutes.
Usually, this is a quick makeshift test for presence of lipids. It is supposed to produce a floating layer of cloudy solution as the ethanol (an organic solvent) dissolves the lipids. Adding the distilled water causes the alcohol dissolved lipids to come out of solution.
However, all this did for the emulsion sample is create a less-cloudy solution with some HEAVIER gunk that has settled somewhere near the bottom of the tube.
I'll give it a spin when I get a chance, but it's been pretty.... interesting.
OK, I tried the OP's thing #2 process and got similar results. I should note that my blender did not pulverise the coffee as finely as the OP's seemed to, however. Also, I filtered the liquid through a paper towel placed in a conical sieve, not an aeropress. After filtration I heated some of the coffee up to about 90 Celsius (in a microwave)
Observations - Cold - Appearance of filtrate was tan, almost opaque liquid like a filter coffee with a dash of skim milk - There were no fine particles visible - Aroma was sweet and fresh - Taste was relatively normal, but seemed slightly more bitter, astringent and woody on the back palate than normal - After 30 mins there were signs of slight oil separation, the liquid was slightly darker and less opaque and some dark sediment had appeared - The oil layer was barely visible and did not have any opacity
Observations - Hot - Coffee immediately looked darker and less opaque than the cold sample, with a developing thin oily film on the surface - As the coffee cooled the film remained and became white and broken in appearance - The cooled hot sample remained significantly darker, clearer and with a much more pronounced oil/wax layer than the cold sample
Hypothesis - The coffee contains high melting point fats (waxes?) that are solid at room temp - The high shear rate of the cold maceration process releases these waxes into suspension and breaks them up into very small particles that turn the liquid opaque and remain suspended (somehow) in the cold liquid - When the liquid is heated to above the melting point of the waxes, they separate out (somehow) and float to the top - Due to the lower shear rate and/or coarser filter medium than the OP's process, the liquid showed sedimentation and produced a less stable emulsion in the cold sample
Possible further tests - Repeat with variations using fine ground coffee produced in coffee grinder - In one variation use same blending process as above - In second variation leave blender off but gently agitate the mix with a stirrer
If my hypothesis is correct then the first variation would be more similar to the OP's results, and the second variation would produce a clearer liquid with a rapidly forming liquid oil layer with little or no waxy component. Further variations could be to repeat the above using a finer filter medium closer to the OP's process. I would expect the main difference here to be removal of the sedimenting fines
Why heating releases the waxes seems unclear. Perhaps the waxes remain bound to insoluble solids, and are only free to escape once they are heated and liquefied
Posted Thu Feb 21, 2013, 6:13am Subject: Re: Weird things I've done lately with coffee:
On the quest for "over-extraction" and "under-extraction":
Grind fine, set up a brew and brew a cup (immersion) that is technically over-extracted. Lido setting 0.25, 12 minute steep.
Same brew ratio, Lido setting 2.0, 4 minute steep.
Yep, brew 1 has all qualities of over-extraction. Brew 2 is pretty much spot on. Technical numbers were right around 20% extraction for brew 2, and about 23.5% for brew 1.
Now, what fraction of brew 1 has to go into brew 2 before you can taste it as trending toward overextraction?
Why would I do something like this?
Well, it had to do with someone telling me all about French Press coffee, and how the fines (the small particles) keep extracting making the coffee bitter. I explained how the small particles actually reach a sort of equilibrium - where I was told flatly that I was wrong (along with a smart phone internet citing, of course, where the particular "expert" went on to say this exact thing I was told - fines continue to extract, making french press coffee bitter over time).
It was on the internet - must be correct, right?
I thought about the old anectdote:
... you have a gallon of wine and a gallon of raw sewage (a pleasant thought, huh). Take the gallon of sewage and add one teaspoon of fresh wine, and describe what you have.
Answer: you have a gallon of sewage.
Now, take the gallon of wine, and add one teaspoon of fresh raw sewage. Now what do you have?
Answer: you have a gallon of sewage.
LOL
The answer with the first couple rounds - about 50% or so before I start getting part elements of overextraction. That's just really a hint, but surprise to me, it took a significant amount of over-extracted coffee to affect the taste. I thought that 5% or 10% would be enough, but it takes quite a bit to do it.
What this tells me is the fines in French Press coffee (even if you have a crappy grinder, and they make up maybe 30% of the grounds) may help tip the brew toward over-extraction because the average grind size is smaller, but the amount of fines probably don't continue to "extract" enough to matter. What matters for extraction in an immersion/infusion brew is the bulk of the size of the grind, the temperature and time at which the coffee is extracted.
Furthermore, I explained that the fines in French Press coffee don't show signs of continuing to extract, because measurement of the strength of the coffee remains constant (at least for the first 45 minutes after fine-ground, gritty French Press coffee is made and decanted). If it continued to "extract" then we would see the beverage strength increase over time.
But, it's an interesting thing to try - let me know if any of you try this and what your taste threshold is.
------------------------------------------ ----------------------------------------- Le café doit être noir comme le diable, chaud comme l'enfer, pur comme un ange, et doux comme l'amour.
"There is no right answer with coffee. There is only the elixir in your cup at the moment you partake."
"...I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind;..." - Lord Kelvin RECIPES thread => http://www.coffeegeek.com/forums/coffee/machines/585708
Posted Thu Mar 21, 2013, 12:36pm Subject: Re: Weird things I've done lately with coffee:
I took a half lb of Colombia Del Patron, roasted it to 2nd crack +30 seconds (a decent rich FC+, not quite Vienna-French, oil didn't appear on the beans for about a week, and approximate Agtron color tiles in the 40's or so).
Then, I took several ~15g samples from the batch, and put the remaining (approximately 148g) into an old club soda bottle with a schrader valve on the end, and sealed up the bottle.
The sameples I did this: -Beans only, vacuum sealed within 30 minutes of roasting -Ground LIDO 2.0 and immediately vacuum sealed. -Ground LIDO 2.0 and vacuum sealed 5 minutes after grinding -Ground LIDO 2.0 and vacuum sealed 10 minutes after grinding -Ground LIDO 2.0 and vacuum sealed 30 minutes after grinding and -Ground LIDO 2.0 and vacuum sealed 1 hour after grinding.
Then, I waited. After about 4 weeks, the bottle gained pressure to around 8PSI.
The vac pac of whole roasted beans took a week before it finally started expanding. I'd estimate it took around 3-4 weeks before it started expanding in earnest.
The ground immediate, 5 and 10 minute packs started off gassing noticeably within about 6 hours, and reached an equilibrium in around 5 days. The 30 and 60 minute "rested" ground coffee packs had about 1/3 the off-gassing of the 0,5, and 10 minute packs, in about 4 days.
I would estimate the most off-gassing after 6 weeks of the packs is the whole beans. Then the ground immediate, 5 and 10 minute packs seem almost indistinguishable from each other, and maybe 80% as much as the whole beans (but they reached this state within days, not weeks). The 30 and 60 minute packs are noticeably less off-gassing, about 1/4 the sealed beans, and 1/3 the fresher ground packs.
Then, I weighed the bottle, released the pressure and re-weighed the bottle - and lost 0.60g of mass. That implies at this particular roast level, somewhere around 0.4% gas and volatiles. I'll let them sit for another week to see if there is any more off-gassing, and then try the coffee. Not expecting much (this now 6-8 week old coffee), but the aroma of the pressure release of the bottle was an aroma shot of pure chocolately heaven - a heady scent that wandered around the room for about 20 minutes before gently dissipating. If the actual coffee tastes even 50% of how the released gasses smelled, I'll be a happy camper.
The reason I did this:
-Trying to see if the Illy figures of CO2 production during roasting are applicable to the coffee once cooled. They say something around 2% of the mass, but I believe it to be much less (essentially almost indistinguishable).
-Trying to see if grinding does anything for off gassing for normal-ish grind level. Mass differences aren't exactly accurate, because if you grind coffee and let it sit, then some of the gasses and some of the moisture leaves the ground coffee. I reasoned that if you vac-sealed ground coffee, you could get an estimate of how much gas is released by grinding. I suspect now that some of the gas is released during grinding, but not as much as I was thinking MIGHT be released.
Maybe some day I'll try a Turkish grind (a grind that goes to tearing the actual cells of the beans apart) and see if that does an immediate gas release.
------------------------------------------ ----------------------------------------- Le café doit être noir comme le diable, chaud comme l'enfer, pur comme un ange, et doux comme l'amour.
"There is no right answer with coffee. There is only the elixir in your cup at the moment you partake."
"...I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind;..." - Lord Kelvin RECIPES thread => http://www.coffeegeek.com/forums/coffee/machines/585708
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
= No New Posts since last visit 