flamable substances in orange rind?

[CC]

I have been aware for a long time that it is possible to ignite a volatile exudate of an orange rind in a dramatic puff of flame. What a great way to impress 8th grade students! (You simply peel off a good sized hunk of rind, light a match, place it about 1/4 inch from the outer surface of the peel and bend/fold the peel so that what's inside the rind squirts out at the flame. Poof! Wizard of Oz!) But I would like to know what that substance is. I haven't been able to discover it. Do other foods contain volatile substances too? Is there any practical use for the material, aside from its obvious use as a weapon? e.g. the state of Florida declaring war on, say, Missouri. "Stand back, he's got an orange peel!"

[Qadgop the Mercotan]

I know the peel contains different alcohols and esters, many of which are flammable. But I'm not sure which exactly it contains.

[Duck Duck Goose]

Well, it's basically just oil, but it also has other stuff in it that, since IANA biochemist, I'm not equipped to discuss, things like "terpenes".
http://www.wiu.edu/users/mftkv/org330/exp3.htm
http://www.deltrex.com.au/products/s144.htm
http://www.floridachemical.com/datas...orangeoil.html

Keep away from eyes.

When you make candied orange peel, you have to be careful not to rub your eyes before you wash your hands.

[Rayne Man]

My Grandmother used to save all the orange peel,dry it off and then use it to make a very good fire-lighter for coal fires.

[Bob Scene]

There's a substance called d-limonene (aka (R)-1-isopropenyl-4-methylcyclohexene) that can be extracted from orange peels and that is commonly used as a cleaning solvent and a hand-cleaner-goop solvent because it has a really pleasant orange smell. Limonene is somewhat flammable (flash point of 115 F), and I wonder if this accounts for the flammability of orange peels.

A lot of people seem to assume that d-limonene is harmless because of the smell, but it's not significantly chemically different from a lot of things that smell bad and that a lot of people would object to working with.

I used to work with paint that contained dipentene, which is a mixture of d- and l-limonene. Dipentene smells bad, and I bet most people wouldn't want to use hand cleaner containing dipentene, but it's pretty much the same as d-limonene. Even though d-limonene may not be any better for you than other unsaturated hydrocarbons, it's a lot more fun to work with because of the smell.