Non-alcoholic Flambe

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Chlorophyte
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Non-alcoholic Flambe

Postby Chlorophyte » Sun Feb 06, 2011 4:43 am UTC

Hello all. Lurked for quite some time but decided to join now that I have a suitably interesting problem.

So, here's the setup. I want to a chemistry demo as part of a science camp for kids, ages 8-15 or so. My idea was to show them a flambe, using some sort of delicious candy e.g. gummy worms. Fire + Candy is always a hit. Talk about what's actually burning (it's not the food), caramelization reactions, and then put it out using CO2 from dry ice just for show. One problem: no *way* am I getting permission to give alcohol for minors on the job. For those who don't know, when you're flambe-ing something the alcohol doesn't fully burn away.

I still like the idea a lot, for showiness and science but I need to find a substitute for the 40% ethanol that's normally used. Obviously you'll be lacking some of the flavors you get from using brandy or such but that's easy to fix by adding whatever flavourings you want to the combustion fluid. Google failed me (really terrible suggestions like lighter fluid), so I decided to research alternatives on my own.

Unfortunately, there's fairly specific requirements that need to be met. First, the fluid needs to ignite and burn cooler than the food starts catching on fire at (440 C maybe?), but hotter than Maillard and caramelization temperatures (about 160 C). Second, it can't leave a really terrible flavour behind; ideally it would actually add something. Third, it can't be stupidly expensive and has to be feasible to source. I'd rather not have to synthesize stuff. Kids camp and all that. Most importantly, it can't be toxic, nor can it have toxic byproducts after combustion. Preferably non-allergenic as well.

This is what I'm most concerned about. I mean, I can read MSDS sheets and FDA data sheets and all that but I don't really feel like poisoning the kids / myself. Don't worry, the plan is to talk to a food science prof on campus before actually serving it to double check.

This list of obvious excluded compounds includes: anything not a liquid at or near room temperature, common fuels (toxic, too hot), fats and oils (too hot, dangerous), and sugar solutions (too hot since if sugar's burning, the sugar will burn...).

So, here are my best candidates so far. Tell me what you think. WRT combustion and ignition temperatures, I should be able to moderate them to a degree by dilution in water as long as they're in the right sort of range.


Glycerol
Pros: Really cheap, ridiculously safe. Nice simple sweet tasty.
Cons: Maybe kinda messy due to viscosity. Not sure how hot it burns, may have issues igniting due to low volatility.

Other sugar alcohols are safe and cheap, but not liquid at room temperature like glycerol.

Menthol
Pros: Mint! Fairly safe. Nicely volatile. Pretty cheap. Awesome "cold" feeling on the tongue.
Con: Relatively low LD 50 (3.3 g /kg), but I'd expect the kids to be ingesting maybe a gram or two once it's burned. Analgesic, which may be an issue with fumes.

Fructone
Pros: Fruity apple taste! No known toxicity! May give delicious reaction byproducts.
Cons: Can't seem to find a public supplier for this. Anyone? I'm from Canada, if that matters.

Propylene glycol
Pros: Super cheap. Little flavour, slightly sweet. Used as a food additive, quite safe, well studied.
Cons: Not really *food*? Do I need to find food-grade versions of this?

1,3-Butanediol
Pros: No flavour. Seems safe.
Cons: May not burn readily. Potentially harder to source. Not convinced by safety data, although it's used in food as a solvent.

Propyl acetate
Pros: Banana flavour! Food additive. Volatile. Available and affordable.
Cons: Listed as a mild skin irritant on the MSDS sheet.

Butyl acetate
Pros: Pear flavour. Food additive. Volatile. Available and affordable.
Cons: MSDS sheet says terrible, terrible things. Internal irritant, potential narcotic, potential poison. Despite this, the LD 50 is higher than ethanol...

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nehpest
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Re: Non-alcoholic Flambe

Postby nehpest » Sun Feb 06, 2011 5:52 am UTC

From some Googling, it seems that MSDS warnings are at least partially based on concentration. Re: butyl acetate's dire warnings, the MSDS for ethanol 100% says:

Ingestion: May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May cause systemic toxicity with acidosis. May cause central nervous system depression, characterized by excitement, followed by headache, dizziness, drowsiness, and nausea. Advanced stages may cause collapse, unconsciousness, coma and possible death due to respiratory failure.


which is similarly scary-sounding. However, the MSDS for ethanol 40% lacks this warning, claiming that there are no health risks associated with 40% ethanol in water.

It seems like the materials prof is going to be your best bet on this.

Regarding fructone, most of the suppliers I saw were China-based, and claim to be closed for Chinese New Year through 14th February. Would your campus be able and willing to supply it for you?
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Re: Non-alcoholic Flambe

Postby evilbeanfiend » Sun Feb 06, 2011 2:12 pm UTC

how much alcohol would be left after you burnt it anyway?
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Chlorophyte
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Re: Non-alcoholic Flambe

Postby Chlorophyte » Sun Feb 06, 2011 3:04 pm UTC

Ok, that's what I figured about the safety. Dose makes the poison and all that. And I'm fairly sure I'll have to dilute anything I use to between 10 and 60% to make sure it's not ridiculously flammable. Except maybe gycerol, but that's food anyways.

As to alcohol left over after Flambe, USDA is saying 75% is retained (http://www.ochef.com/165.htm). Yikes, that's really high... I honestly wouldn't care were it *my* kids but yeah, not happening with job and parents involved.

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Re: Non-alcoholic Flambe

Postby ThePragmatist » Sun Feb 06, 2011 3:10 pm UTC

Chlorophyte wrote:Ok, that's what I figured about the safety. Dose makes the poison and all that. And I'm fairly sure I'll have to dilute anything I use to between 10 and 60% to make sure it's not ridiculously flammable. Except maybe gycerol, but that's food anyways.

As to alcohol left over after Flambe, USDA is saying 75% is retained (http://www.ochef.com/165.htm). Yikes, that's really high... I honestly wouldn't care were it *my* kids but yeah, not happening with job and parents involved.


Is 10% alcohol even flammable?
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Chlorophyte
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Re: Non-alcoholic Flambe

Postby Chlorophyte » Sun Feb 06, 2011 3:36 pm UTC

Sorry, I should have clarified. No, 10-15% alcohol is not flammable, you have to use 40% for flambe-ing while 60% makes fireballs :twisted: . The lower limit was potentially for more flammable substances.

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Re: Non-alcoholic Flambe

Postby mercutio_stencil » Mon Feb 07, 2011 8:06 am UTC

It doesn't quite fit your criteria, but you could use butane. Yes, I know it's a gas, but it would be surprisingly easy to get it to work well, or at least look impressive.

I'd start by hiding a butane refill canister up your sleeve (they're kids, this might fool them), then placing the gummy worms in the bottom of a big metal bowl. Then, distract the kids while you fill up the bowl with butane. As long as you're quick, you should be able to get a nice fireball out of it.

I don't think it would actually do anything to the candy, and it certainly wouldn't last long enough to be put out with dry ice, but it would be dramatic and that counts for something.

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Re: Non-alcoholic Flambe

Postby ++$_ » Mon Feb 07, 2011 9:09 am UTC

My suggestion is that you use ethanol and then keep the candies warm (78-100 degrees C) for a while after they are lit in order to evaporate away the residual ethanol.

One thing to keep in mind is that the flame temperature is not the thing that you want to know about. Ethanol burns very hot -- probably 800-1000 degrees C. (This lovely book [Schmidt and Symes, The analysis of burned human remains] suggests that almost everything organic burns at 800-1000 C in air, with a few rare exceptions that burn hotter.) The reason an alcohol-soaked object is not charred is that the alcohol and the water used to dissolve it evaporate extremely rapidly from the object, taking away heat and keeping the object relatively close to 78 degrees (the boiling point of ethanol). If you use something with a higher boiling point, the object will be heated to a higher temperature.

Glycerol: Boiling point is 290. The sugar will be charred.

Menthol: I'm pretty sure that eating something bathed in concentrated menthol would be a rather extreme gustatory experience. Your typical hard candy mint is going to be something like 0.1% menthol by weight, so 1 gram of menthol contains the minty freshness of approximately 100 candies. That would be really overpowering. Besides, it boils at 212 C, which is too high.

Fructone: This is used as a commercial fragrance. Those fragrances are seriously powerful and the odor is overwhelming at high concentrations. This site lists the "average maximum concentration" in hard candy as 20 parts per million (and this is 20 times the "usual" concentration, which is 1 ppm). If you had a candy soaked in this, putting it anywhere near your nose or mouth would probably cause you to vomit.

Propylene glycol: Boiling point is 188, which is pretty high (as parts of the candy will get hotter than this temperature) In addition, you'll have to convince the parents that it's okay for their precious kids to eat antifreeze. This is going to be a tough sell.

1,3-butanediol: Boils at 207 -- too high.

Acetate esters: These have the right physical properties, but they are powerful fragrances. If you put a candy soaked in the compound into your mouth, I expect that it would be pretty repulsive (probably not as bad as fructone, but maybe bad enough).

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Re: Non-alcoholic Flambe

Postby p1t1o » Mon Feb 07, 2011 12:27 pm UTC

So you're not allowed to use pretty minor amounts of alcohol, but you are allowed to light fires? And feed them candy from a sciene experiment?

I know, if it was me, the kids would be in there roasting marshmallows off a magnesium flame, but are they seriously saying that?

**EDIT**
Also, in my experience, menthol vapour has approximately the same effect as tear-gas, you dont want to be burning a bunch of it indoors with a bunch of kids!!

Thing is, ethanol is probably the safest thing to use in any case...

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Velifer
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Re: Non-alcoholic Flambe

Postby Velifer » Mon Feb 07, 2011 1:52 pm UTC

Chlorophyte wrote:Talk about what's actually burning (it's not the food)

Just burn the food.

Take a match to a sugar cube... not much happens. You might be able to melt it with a candle. Next, rub a little ash on a corner of the cube, try again. Pretty blue flame, icky black goo.

Slowly heat a pan of sugar with a propane torch to make caramelized hard candy. Share and Enjoy.

Build a lesson around catalysts, reaction rates and conditions to get things just right, Maillard reactions, and tooth decay.

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Re: Non-alcoholic Flambe

Postby p1t1o » Mon Feb 07, 2011 2:10 pm UTC

Screaming Jelly Baby?

Sugar(Jelly baby)+oxidizing agent(molten potassium chlorate)=flames, smoke, "screaming", delicious smell.

Downside is, you cant eat the remains :(

Was a staple when I was at school.

http://www.youtube.com/watch?v=MUX9M8sCUqc
http://en.wikipedia.org/wiki/Screaming_jelly_babies

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Re: Non-alcoholic Flambe

Postby Jakell » Tue Feb 08, 2011 7:08 am UTC

Leaving the topic of fire, you could perhaps try liquid nitrogen icecream? I do not know if you have access to liquid nitrogen, but if you had roughly 5 liters of LN2, a quart of milk, a quart of cream, and a pound of sugar, you can make a healthy dose of icecream. Add vanilla extract or any number of other flavors and you are set.

And back to fire, could you burn vanilla extract? I do not have any good stuff on hand right now, but Mint Extract (89% alcohol) burns really really well it seems. It ought to be quite edible too, and I do not consider it "alcohol" alcohol, more of a confectionery chemical.
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Re: Non-alcoholic Flambe

Postby idobox » Tue Feb 08, 2011 11:08 am UTC

p1t1o wrote:Sugar(Jelly baby)+oxidizing agent(molten potassium chlorate)=flames, smoke, "screaming", delicious smell.

What would happen if you poured water in the pan, and then dropped some metallic sodium or potassium?
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Re: Non-alcoholic Flambe

Postby p1t1o » Tue Feb 08, 2011 1:14 pm UTC

What do you mean? Do you mean fill a pan with molten potassium chlorate and water and chuck in sodium along with the jelly baby?

Not sure how sodium would react in the presence of both water and potassium chlorate, water wants to reduce the sodium to sodium hydroxide, the potassium chlorate wants to oxidise it to, well, sodium chlorate I think. Depends on relative rates of reaction, of which Im unsure.

There will be several competing reactions including (excuse the stoichiometries, they are unecessary at this point):
Na + H2O -> NaOH + H2
Na + KClO3 -> NaClO3 + K
K + H20 -> KOH + H2

The NaClO3 is free to react with the jelly baby, just like the KClO3, but will likely be less impressive.
As for any reaction of Na/K + jelly baby, thats anybody's guess...possibly some sort of glucose salt from reaction with hydroxides.

IMO, essentially you'd just have the two reactions going off in the same pan, though possibly with their rates retarded by the competing reactions. Im not sure it would be any more impressive than just sticking to one or the other - and just chucking sodium in water is far too boring for purpose here, been there, done that psshhhht...

**EDIT**
It definitely would increase the danger though, having popping hydrogen spitting molten oxidiser and burning sugar over the place...

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idobox
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Re: Non-alcoholic Flambe

Postby idobox » Tue Feb 08, 2011 5:08 pm UTC

I was just thinking about putting mettalic sodium in water. I had the idea reading your post.
Na + H20 -> NaOH + 1/2 H2 + heat
heat + H2 + O2 -> flames, or possibly messy explosion.
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Re: Non-alcoholic Flambe

Postby Carnildo » Wed Feb 09, 2011 6:27 am UTC

Jakell wrote:And back to fire, could you burn vanilla extract? I do not have any good stuff on hand right now, but Mint Extract (89% alcohol) burns really really well it seems. It ought to be quite edible too, and I do not consider it "alcohol" alcohol, more of a confectionery chemical.

The vanilla extract I've got is 35% ABV. You'd need to spike it with some high-alcohol stuff to get a proper flambe level -- which you'd want to do anyway, to dilute the vanilla flavor and keep the cost down.

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Re: Non-alcoholic Flambe

Postby wbeaty » Wed Feb 09, 2011 6:54 am UTC

Hydrogen foam, w/the gas being pumped in by an aquarium airstone or perforated metal tube?

:)

Trouble is, "lecture bottles" of hydrogen are fairly expensive, and welders' hydrogen even more so.
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Re: Non-alcoholic Flambe

Postby iChef » Sat Feb 12, 2011 3:04 am UTC

If you just want to get into the chemistry of carmelizing sugar you can make creme brulee. Make a bunch of small dishes of vanilla custard covered in brown sugar and torch 'em with a propane torch. You get to play with fire and get tasty treats, not quite as impressive as giant fireballs, but still fun.
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Re: Non-alcoholic Flambe

Postby Chlorophyte » Sat Feb 12, 2011 3:28 am UTC

Ok, thanks for all the help guys. Creme brulee is a solid idea. I may do that, or just find another experiment. I'm loving the Home Experiments sticky.

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Re: Non-alcoholic Flambe

Postby 2385a4 » Mon Feb 14, 2011 12:57 pm UTC

This is quite an interesting question. Essentially you want to know of a chemical that is fairly flammable, has low toxicity, and probably a boiling point well below 200°C. It should ideally be less intoxicating than ethanol, and should not taint food. (Oh, and also cheap!)

This is something of a challenge. To restrict our scope, and eliminate things that are likely to produce seriously nasty combustion products, let's limit ourselves to C, H and O. The straight alkanes are largely too flammable, taint food, and the liquid ones are very intoxicating and irritating as well. Ethylene glycol is too toxic, and most of the other glycols are not flammable enough. Carboxylic acids have strong flavours and high boiling points. The mono-alcohols have moderate toxicity and good flammability, but they are pretty well all intoxicating to some degree -- mostly, more so than ethanol. The aldehydes mostly taste quite nasty. Hmm, ketones may be a good place to start.

Your suggestion of propylene glycol is fairly good, at least in being very low toxicity, non-intoxicating, and non-tainting. However the boiling point at 188°C is somewhat marginal, and it isn't really all that flammable, and it is a hygroscopic liquid that rapidly becomes less flammable as it absorbs moisture from the air. In open air, you may have to significantly pre-heat it to get reasonable combustion. (Obviously, whatever we come up with, you're going to need some rehearsals!)

Another possibility may be acetone. Boiling point is 56°C, and it is extremely flammable; you may want to cut it a little with water to slow it down a bit. Not particularly tainting (most people find the odour pleasant, at least in moderation.) Now you may be thinking "it's an industrial solvent, I'm not putting that on food!" but actually the toxicity of (pure!) acetone is much less than people realise; it occurs in the body naturally as part of the ketone cycle and so has no known carcinogenic or teratogenic potential, and an unalarming LD50 of around 1g/kg. It is on the GRAS list as a permitted excipient in pharmaceuticals, and has also been used as a food additive. However, while 1 g/kg is not particularly dangerous, acetone is more intoxicating than ethanol, not less.

n-butanol is another choice. Boiling point 117°C, very flammable (not as bad as acetone, which is just as well as it is also less miscible with water), a distinct but not unpleasant odour (unlike some of the other butanols), and low toxicity (only about twice as toxic as ethanol, and occurs naturally in many foods.) Unfortunately, like acetone, it is actually somewhat more intoxicating than ethanol, taking about 1/6 as much to cause intoxication.

OK, lets move on to esters. Hmm, butyl acetate looks good. Boiling point 126°C is a little on the high side; very flammable, but not quite as dangerous as acetone; approved food additive that occurs naturally in several types of fruit, and has a smell of bananas; and low toxicity (the LD50 of 10.5 g/kg is about the same as, or slightly higher than, ethanol!) But the odour is very powerful, and may be unpleasant at high concentrations.

Ah wait, here's an ester with a relatively weak odour: ethyl acetate. Boiling point 77°C, extremely flammable and only slightly miscible in water; approved food additive and occurs naturally in some fruit (but especially in wine); slightly less toxic and slightly less intoxicating than ethanol (when ingested, it very rapidly breaks down to 52% w/w of ethanol, rest acetic acid i.e. vinegar). Has an ethereal, slightly fruity odour (if you've smelled non-acetone nail polish remover, you've probably smelled this) but it is much less powerful than other esters and a residual trace in food may not even be noticed.

I'd suggest trying the ethyl acetate, but be very careful of its low flash point and easy ignition. And do tell us how it tastes :)
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Velifer
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Re: Non-alcoholic Flambe

Postby Velifer » Mon Feb 14, 2011 2:21 pm UTC

2385a4 wrote:This is quite an interesting question.

AND YOUR ANSWERS ARE DANGEROUS AND STUPID
Flipping through chemical abstracts does not make you a food scientist.
Reading a line about LD50 does not make you an expert in toxicology.
You want to risk damaging yourself, fine, go have fun.
Do not serve adulterated food, especially not to children, and especially not to someone else's children.
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Re: Non-alcoholic Flambe

Postby 2385a4 » Mon Feb 14, 2011 3:35 pm UTC

Velifer wrote:
2385a4 wrote:This is quite an interesting question.

AND YOUR ANSWERS ARE DANGEROUS AND STUPID
Flipping through chemical abstracts does not make you a food scientist.
Reading a line about LD50 does not make you an expert in toxicology.
You want to risk damaging yourself, fine, go have fun.
Do not serve adulterated food, especially not to children, and especially not to someone else's children.

(Emphasis added.)

You might like to read what I wrote before flaming.
Cheers.
Beulah.

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Re: Non-alcoholic Flambe

Postby gorcee » Tue Feb 15, 2011 9:49 pm UTC

So let's take a look at the risk-reward here.

Best Possible Reward: You look really cool to a bunch of ~10 year old kids who are already enrolled in a science camp

Worst Possible Risk: A kid eats a candy you coated with some shit and lit on fire, and gets sick. The kid might not even get sick from the candy. He's 10 and at camp. There's a good chance he ate a worm just to impress his friends. But he's sick, and if he tells his mom he ate a worm, he'll get in trouble. So he doesn't tell her that. Instead, he tells her about your experiment. The parent, having grown up in the 80s and 90s where we were all led to believe that we're all a completely unique and special snowflake (and as we got older, realize that this isn't true and use our children as proxies to hold that belief instead), lawyers up and sues you and the camp. Presumably, because you're a volunteer, it's argued that you're not protected by vicarious liability so the camp also files suit against you. So now you've got two lawsuits, and your best defense on why you chose such a demonstration is because some dude on the internet with no credentials posted an impressive sounding paragraph. He might even be right. But the jury is composed of your peers, 20% of whom, statistically, think that the Earth is 6000 years old, and think that CSI: New York is a documentary. So all the science hogwash is lost on nine of the jury members, which is the least required for judgment in a civil suit in your jurisdiction. So now you've been sued, and because you don't have any real money, you declare bankruptcy. Your credit score drops to 410, so you can't even move someplace else to find a job because you'll never pass the rental credit check. Not that that would matter, because no one will hire a dude that got sued for feeding kids some candy covered in spooky chemicals. The lawsuit process will take 5 years with appeals, and will be such an ever-present factor in your life that you're gray-haired by 32.

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Re: Non-alcoholic Flambe

Postby p1t1o » Tue Feb 15, 2011 9:56 pm UTC

Wasn't that the backstory to most high school chemistry teachers? hawhawhaw


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