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Caffeine 'Dipstick' Test for Coffee 110

An anonymous reader writes "Researchers at Washington University School of Medicine in St. Louis are developing a quick test for caffeine that works even with hot beverages and plan to adapt their technology to a simple ('dipstick') test that can be used to check for caffeine in a variety of drinks. The key to the caffeine test comes from llamas and camels since these camelids happen to be among the few creatures whose immune systems can produce antibodies that aren't destroyed at the high temperatures common to brewed beverages. The researchers reasoned that if they could create heat-resistant camelid antibodies that reacted to caffeine, they could potentially build a durable assay suitable for use almost anywhere."
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Caffeine 'Dipstick' Test for Coffee

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  • ...just WTF is a "durable assay suitable for use almost anywhere"???
  • by guitaristx ( 791223 ) on Friday May 12, 2006 @01:46PM (#15319448) Journal
    It's a wooden stick with the words "Not enough" imprinted on it.
    • Urine tests (Score:5, Funny)

      by Seoulstriker ( 748895 ) on Friday May 12, 2006 @02:11PM (#15319732)
      They should make these sticks suitable for use in a way similar to pregnancy tests: pee on the stick to see the concentration of caffeine in your system.

      Blue means not enough
      Pink means just right
      Black means you're peeing coffee.
      Brown means you put it near the wrong orifice.
      • Brown means you put it near the wrong orifice.
        So, that basically meens you have the shakes from too much coffee, and you can kiss coding goodbye for awhile.
    • by Sponge Bath ( 413667 ) on Friday May 12, 2006 @02:28PM (#15319892)
      It's a wooden stick with the words "Not enough" imprinted on it.

      You use your penis to test coffee?

      • That reminds me of an old joke . . .

        There's this guy named Jack, and he has a girlfriend named Wendy. Jack loves Wendy a lot. To prove how much he loves her, he gets "Wendy" tattooed on his penis. When it's erect, it says her name, and when deflated, it reads "Wy". So, when she sees her name on his masculine member, she is overwhelmed.

        He pops the question, and she accepts. So Jack and Wendy decided to go to Jamaica for their honeymoon. Once there, they try out all the local culture,including a nude beach

  • roast paradox (Score:5, Interesting)

    by yagu ( 721525 ) * <> on Friday May 12, 2006 @01:46PM (#15319451) Journal

    Great, I first had to look up assay:

    3 : analysis (as of an ore or drug) to determine the presence, absence, or quantity of one or more components
    (from Merriam Webster).

    Anyway, sometimes when I drink coffee I seem to have an entirely opposite reaction and am overcome with sleepiness. It only happens occasionally, and counterintuitively it always seems to be a very strong brew of some Starbucks blend. After doing a little research I discovered what you might expect to be a stronger (caffeine-wise) coffee is actually the weakest.

    Turns out the darker the roast, the longer the beans have to be roasted to become that dark. And the longer the beans are roasted, the more caffeine is destroyed in the process. So, while a roast may be described as bold, but it doesn't necessarily mean it has extra kick. I prefer the bold roast taste, but have taken to preparing much lighter roasts for my morning kick-start.

    Interestingly enough, this could also explain why I am positively higher than a kite when I drink someones A&P Maxwell House Drip grind coffee. It is a bland light looking roast/blend, but it can really have a kick.

    Here's one page [] that answers some questions about caffeine.

    • Alton Brown did a show about coffee, and what he had to say about caffiene content vs intensity of roast agrees with you. Also, I, too often feel drowsy from a cup of dark roast coffee.

      Fortunately Starbucks on campus had a somewhat lighter than normal "Papua New Guinea" variety available for the last 2 weeks of the spring term. This coffee was both a refreshing beverage and high test fuel. I hope it is available all summer, as the Sumatra is tasty but makes me a bit sleepy.
    • by gEvil (beta) ( 945888 ) on Friday May 12, 2006 @02:37PM (#15319996)
      Anyway, sometimes when I drink coffee I seem to have an entirely opposite reaction and am overcome with sleepiness.

      Lay off the Irish coffees there, Sparky.
    • It's not *only* the darkness of the roast, but also the serving size. After all, a proper dark roast espresso is generally served in a *much* smaller cup than a good mug of a lighter roasted filter brew.
    • Re:roast paradox (Score:2, Interesting)

      As a roaster (hobbyist) I find the best of both worlds can be achieved by working with a "Black and Tan" roast of sorts.

      Caffeine aside, you'll find that the lighter roasts have all kinds of flavor profiles (floral, citrus) that combine very well with those of a darker roast (chocolate, nutty*, "earthy").

      I've always enjoyed coffee, but a whole world was revealed when I started raosting it myself. It makes the best coffeehouse brew taste like sludge.

      * please, no Austin Powers jokes.

    • Turns out the darker the roast, the longer the beans have to be roasted to become that dark. And the longer the beans are roasted, the more caffeine is destroyed

      Not to mention that diff't coffee has diff't amounts of caffeine -- regional varieties are not all the same (which is why colombian coffee is diff't than mexican coffee, for example), and there are two main families of coffee -- arabica (which people are trained to think is 'the best' coffee), and robusta --- robusta is generally considered not
    • There is also a big difference in caffeine levels between Arabica and Robusto beans. Robusto is the cheaper bean, but more bitter, and the big companies of course went for cost reductions, thus a pretty good bet that your Maxwell House is Robusto. (They'd be making a big deal out of Arabica on the label if they used it.)

      Starbucks, going the quality route, brings the Arabica bean to the masses.

      So drink up!
    • Turns out the darker the roast, the longer the beans have to be roasted to become that dark. And the longer the beans are roasted, the more caffeine is destroyed in the process.

      This is a true revelation. So I went running to my Merck Index, and read this about Caffeine:

      Hexagonal prisms by sublimation, m.p. 238 C. Sublimes at 178 C.

      I'm not sure at what temperature coffee is typically roasted at, but I'll bet it's not much less than than 178 C. If so, much of the caffeine is just wafting away...

      • So theoretically, if one wished for a real kick in the pants, breathing roasting coffee vapors would do wonders. Hmmmm .... the coffee bong. (I need to run off and start the patent paperwork now ...)
    • Easy solution: buy caffeine pills in bulk, crush in a mortar and keep in a bowl next to the sugar. Drink whatever you want and season to taste.

      In fact, just mix it in with the sugar and some MSG, and you have flavour, energy and hyperactivity all in one convenient serving!

    • Interestingly enough, this could also explain why I am positively higher than a kite when I drink someones A&P Maxwell House Drip grind coffee. It is a bland light looking roast/blend, but it can really have a kick.

      What's far more likely is that the el-cheapo Maxwell House uses robusta beans and Starbucks uses arabica beans. Rubusta beans have about twice as much caffeine in them as arabica beans.
  • We need a dipstick that will tell us the caffeine is up to snuff. I don't want to be short changed on my caffeine and would be happy to see something akin to a thermometer poping it's cap, letting me know my fix is just a wicked as I need it to be.
  • by fragmentate ( 908035 ) * <[jdspilled] [at] []> on Friday May 12, 2006 @01:52PM (#15319517) Journal
    I already have a test...

    If after 15 cups of a beverage (non-alcoholic) in one hour I don't have the shakes, there's not enough caffeine.

    Cost: $0
    Research time: 1 hour.
    Damage to Camels and Llamas: less than .02%

  • easier test (Score:5, Funny)

    by gEvil (beta) ( 945888 ) on Friday May 12, 2006 @01:58PM (#15319579)
    I've got an easier one. The black handle means 'caffeine.' The orange handle means 'no caffeine.'
    • Unless the gas station attendant is bored and looking for some fun.

      If you're careful you can ease the dosages up so the heavily caffinated come off of it and the non-caffinated start to need it.
      • It's fairly safe to assume that if you're buying coffee at a gas station you're buying it purely for the caffeine.
        • Again a lot of it depends on how much the employees like the job (directly tied to the ratio of nice friendly customers to jerks), but the coffee at the Speedway where I worked was pretty good. Not quite a fancy candy-coffee like the local coffee houses, but not a bad cuppa.

          One of the other stores where I subbed in occasion (ie lotta jerks who got switched to decaf), the coffee never tasted quite right because the machines weren't cleaned as often as they should have been nor were the grinders and percolato
      • That's always a fun prank to play on your fellow office drones. Over a period of a few weeks, slowly taper the blends in all the pots so they all contain decaf. Once everyone has been sufficiently weaned off the caffeine, abruptly switch back to the fully leaded stuff. Sit back and watch the fireworks.

        I did this to myself as an experiment some years back - completely gave up caffeine for Lent (no coffee, tea, soft drinks, chocolate, Excedrin, etc), and then on Easter Sunday I went to the local coffee s

    • Decaffeinated doesn't mean "no caffeine"; it just means "less caffeine". That's why it's called "Decaffeinated" instead of "Caffeine Free". The process for removing the caffeine gets out most of it, but not quite all. So if you're quitting America's (second?) most popular addictive stimulant imported from Colombia, don't look for decaf, look for caffeine free.
  • Ugh (Score:5, Funny)

    by voice_of_all_reason ( 926702 ) on Friday May 12, 2006 @02:03PM (#15319632)
    Friend: "Hey, that coffee smells good. What kind is it?"

    Me: (taking a deep breath) Now? Camel-flavored.
  • by Anonymous Coward on Friday May 12, 2006 @02:04PM (#15319638)
    I've found that most people who are that worried about the amount of caffeine in their coffee really are dipsticks.
  • by idontgno ( 624372 ) on Friday May 12, 2006 @02:04PM (#15319643) Journal
    You dip a camel... or llama... in your coffee and somehow that tells you (A) whether it's hot, and (b) whether it's caffeinated?

    And then you drink the coffee? Do you at least take the camel or llama or alpaca or whatever out of the coffee first?

    I wonder which llamas work best. Red, Mexican Whooping, or Guacanos?

    Oh, yeah, obviously, you use a "2-L" llama. I don't think most Tibetians would appreciate you using a "1-L" lama.

  • by Billosaur ( 927319 ) * <wgrother.optonline@net> on Friday May 12, 2006 @02:08PM (#15319693) Journal
    The key to the caffeine test comes from llamas and camels since these camelids happen to be among the few creatures whose immune systems can produce antibodies that aren't destroyed at the high temperatures common to brewed beverages.

    ...for Perl programmers. We trust anything that can pass the llama or camel test.

  • Hmm (Score:3, Funny)

    by Is0m0rph ( 819726 ) on Friday May 12, 2006 @02:09PM (#15319705)
    I need a stick that will give me caffeine and alcohol percentages so I can get that half and half mix of Redbull/Monster and vodka just right.
    • I believe they already have a device for getting your mix right, it's called either a graduated cylinder or a measuring cup depending on whether you buy it at the chem shop or at the local grocer.
      • Hehe I don't want to measure with a graduated cylinder I need a high tech dipstick! How old school...
        • The "high-tech" device you're looking for is a hydrometer. Any brewing supply company will sell you one -- even a "special high-tech" one with alcohol percentage graduated on it.
  • by smellsofbikes ( 890263 ) on Friday May 12, 2006 @02:27PM (#15319867) Journal
    I think it's really cool that they said "we want high-temperature biologicals: where can we get them?" and went and found them in temperature-resistant animals. It's obvious, in hindsight, but it's a great idea.

    When Kary Mullis invented the polymerase chain reaction [] for amplifying DNA to detectable levels -- which is more or less responsible for the viability of genetic engineering as a discipline -- the original system was extremely expensive because it used enzymes that got cooked in the high-temperature portion of the cycle. So they went to Yellowstone and found similar enzymes from creatures that lived in geyser pools, which dealt very well with those high temperatures, and that made PCR a viable research tool. So the idea was already there, but -- camels. Dude. I don't think I would ever have made that particular leap.

    By the way, the reason they didn't just go back to Yellowstone is because while mammals and birds produce lots of antibodies, other animals either don't at all or don't in a manner that's well understood. (Or at least that's what they were teaching when I took immunochemistry.) Plants and bacteria don't produce them at all. Since an antibody is both incredibly specific and incredibly avid for a given chemical, you can stick their butts to a substrate and their front ends will stick out just waiting to attach to their chosen molecule -- much like a leech, if you've ever seen how they work when they're in water.

  • TFA: those who are highly sensitive to caffeine can feel its stimulant effects for as long as 20 hours

    Here I am on my second pint of Timmy's(*) in two hours, longing to be a sensitive type.

    (* Coffee [])

    • My girlfriend's sensitive to coffee. It's not a state you want to be in. Yes, a cup of coffee would send her high for days. It'd also make her faint, give her headaches, make her veins stand out, etc. etc.

      Be thankful for small mercies!
  • I mean, it's nice to know but I tend to go by the adjust until satisfied method. I mean, would you let a good cup of coffee go to waste just cause it only has half the caffeine? Of course not! You drink it and go get another! =)
    • I think this would be more useful for people who order decaf and want to make sure the waiter/clerk/whoever hasn't been a dipstick and given them regular (or some mix of regular and decaf) instead.

      I know someone who has no trouble drinking regular coffee in the morning, but just one cup after dinner means the difference between sleeping well and tossing and turning all night.
  • Jane: Doctor, what does the test say? Am I pregnant?
    Doctor: No, Jane, you're not pregnant. But according to this stick you should switch to decaf.
  • by Java Ape ( 528857 ) <> on Friday May 12, 2006 @03:35PM (#15320503) Homepage
    When I was a grad student in Biogeochemistry some years ago, many of the students were serious caffeine junkies. Since Think-geek wasn't around to supply everything from bubble-gum to body-wash with a cafeine kick-start built in, they found another solution.

    Next to the coffee pots were all the usual additives, and nice little sugar bowl containing a mixture of pure caffeine and powdered sugar, labled "Caffeine: 100mg/tsp". The average cup of joe contains about 100mg naturally, so a couple of teaspoons of this sweetener would make expresso look like diet cola!

    The truly frightening thing was watching some students add four or five teaspoons to their double-brewed black death fluid in the mornings.

    • "Biogeochemistry"? You just made that up.

      When I was a grad student in Physioarchaeanthropology we would create tradition Egyptian coffee brews for kicks.
      • LOL, it sure sounds like a made up science, but it's not! Google it, you'll find it's a very active field of inquiry. Of course, I wanted to get an additional degree in Astrophysics, just so I could claim to be a Biogeoastrophysiochemist, but my wife wouldn't go for it!
        • Biogeoastrophysiochemist

          My wife is a Biogeoastrophysiochemistectarianologist. She observes biogeoastrophysiochemistectarian meetings on Sundays. They meet nearby. Her dissertation covers the effects of caffeine on biogeoastrophysiochemistectarian speculations regarding climatological changes and implications on Saturn's moons. Caffeine intake is strongly correlated with wild-ass guesses and hand-waving.

          IT'S A FACT!
        • English is not German, and you can't just cram all of your words together to make one uberword simply because you think it'd look cool. So cut it out, buddy. :)

    • Speaking as someone who has tried this, I say it is not practical.

      I drink a lot of coffee, and during finals I'd have to eat caffeine pills and ephedrine (and still sleep through half my final)

      I tried to make things easier by dissolving the contents of a 325mg gelcap of caffeine in a pot of coffee. That little pill ruined my whole pot of coffee. Completely unspeakably bitter nasty chemical nausea-inducing nightmare, with only a 30% caffeine boost. I was poor and pressed for time so I drank it anyway.


      • I'd recommend studying through the semester instead of trying to cram a month's worth of studying into one evening. You get more sleep, and you're more apt to actually remember that information that's probably somehow relevant to your degree.

        But sure, I guess throwing money away on stimulants works, too. Kinda.
    • Where did they get the caffeine in such a form? The only way I know of getting it is in little bitter pills.
      • One advantage of working in University chem labs, particularly on the biochem end of things is the ready availability of lots of reagent-grade bioactive compounds. Purified caffeine is readily available from chemical suppliers, and not terribly expensive. Caffeine is quite bitter, but most over-the-counter pills have some very nasty-tasting addatives to discourage just this sort of dumb behavior. One cavaet about reagent-grade caffeine: I haven't looked at the MSDS in some time, but I seem to recall that
  • by macz ( 797860 ) on Friday May 12, 2006 @03:36PM (#15320511)
    Eliminate the coffee, and its subsequent need to be tested, altogether?
  • by Anonymous Coward on Friday May 12, 2006 @03:53PM (#15320685)
    it is fairly common in the evironmental remediation industry to test for caffeine in soil samples and ground water, as a way to determine location of sewer leakage.

    you see, caffeine goes right through the body and leaves as caffeine. In most of the world, there are no natural caffeine sources. So, if you detect it, there is a good chance it came from that possible faulty sewer line.

    usually these tests are done in a lab, but quick, on-site tests via something like this could provide an easy 1st pass diagnosis.

    cue the jokes, but this just goes to show that there could well be other uses of this product.
    • I just wanted to say thank you for providing one of the very few non-idiotic comments in this thread, and the only one to suggest that somebody actually bothered to give a little bit of thought to the original post.

      Kudos to you.
  • I thought the limit was when I saw a warning on a peanut butter that it may contain nuts. Now this. Check coffee for caffeine. Right. It is coffee. What do you think is going to be in it?

    Decaf? That stuff still around?

    If you don't want caffeine drink WATER! Whats next. A test that tells you chocolate has calories. Nicotine detector for cigarets?

    I know their is intelligent live out there because it doesn't visit us.

  • by blamanj ( 253811 ) on Friday May 12, 2006 @07:20PM (#15322272)
  • There's definately caffeine in coffee.

    (still no cure for cancer)

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