I have no idea what I just saw

June 14, 2008 6:29 AM

What was this guy on the street doing with a black iron pot on a spit that produced a gunshot-like sound?

I was walking around Shanghai and I saw a man turning an urn-shaped black iron(?) object on a spit, with a small fire burning underneath / around it. It was all set up on a fairly busy sidewalk. He then pulled out what looked like a mesh laundry bag, and a small child nearby put his hands over his ears and started running like he knew what was about to happen next. I didn't actually see what followed (I kept walking), but a few seconds later it all made a sound about as loud as a gunshot.

So, uh, what the heck was this guy doing?

posted by 0xFCAF to grab bag (18 comments total)

Making popcorn. You used to see them all the time up north here too, but it's a rare sight in beijing these days (though I don't get out much). I'll do an image search in a sec and see if I can find some linkage.
posted by Abiezer at 6:55 AM on June 14, 2008

Here you go; off a GIS for 爆米花: an article on ten memorable street snacks of ye olde Beijing; crusty old lad with popcorn maker second pic. Was that about what you saw?
posted by Abiezer at 6:58 AM on June 14, 2008

I even found a video. Awesome!
posted by 0xFCAF at 7:03 AM on June 14, 2008 [1 favorite]

Sorry to spam away; here's an article and some pics entitled "Disappearing trades: country popcorn makers" which describes the process (in Chinese). If you don't read it I'll happily post a quick summary if you want.
posted by Abiezer at 7:04 AM on June 14, 2008

Ooh, your video is the best answer! Mark yerself :D
posted by Abiezer at 7:05 AM on June 14, 2008

I don't read Chinese, but the whole thing looks outlandishly dangerous. Is the bag to catch the popcorn, or the lid of the pot thing?
posted by 0xFCAF at 7:06 AM on June 14, 2008

I'll have to read it properly to see; I've only ever walked past them really. I always assumed they made the pressure burner thing out of old truck parts or something. Will have a scan of that article and see what it says.
posted by Abiezer at 7:10 AM on June 14, 2008

Yeah; reading that it does sound pretty hairy. It describes setting the thing up (a bellows affair, the fire and then the burner thing itslef which he says is made out of scrap iron - one end for putting in the corn and sugar, the other with that clamp affair and maybe a temperature gauge). then says when it's done he releases the clamp and lets the puffed corn blow out into the sack tied onto the end of the basket. Apparently what draws the kids is that as well as the noise, traditionally they can keep the stray popcorn that gets blown on the ground rather than staying in the sack - good advertising! It says the kids scrabble around eating the popcorn dirt and all oblivious to the hot smoky oven. No wonder they won't have them in the big towns any more.
posted by Abiezer at 7:21 AM on June 14, 2008

Clearly, some one needs to make a post in the blue about this - fascinating. I'd like to know what the other street snacks were, too.
posted by Liosliath at 8:15 AM on June 14, 2008

I'm pretty sure he is not popping "popcorn". He is making puffed rice.
posted by hecho de la basura at 8:23 AM on June 14, 2008

I have seen them making this at T&T in Toronto. It's good stuff!
posted by SNACKeR at 8:42 AM on June 14, 2008

So, if I understand this correctly, that urn thing is sealed and as it heats up, the pressure increases but nothing "pops" until you release the pressure? That is *so* cool.
posted by Slarty Bartfast at 9:43 AM on June 14, 2008

I'm pretty sure he is not popping "popcorn". He is making puffed rice.
No, it's popcorn and says so in the linked texts.
posted by Abiezer at 9:49 AM on June 14, 2008

I wonder if the variety of corn they use doesn't pop as easily as "popcorn"? The pressure vessel technique can pop or puff various types of grains like rice or wheat or even dough. (aka. rice krispies, sugar smacks, capn crunch) It's a nifty process. The grains in the pressure chamber get hot and full of steam. When the chamber opens, the pressure drops, the steam quickly exits the grain and pulls it apart.
posted by kamelhoecker at 10:22 AM on June 14, 2008

Exactly. Popcorn does not need to be heated under pressure to pop. Other grains may be heated under pressure and forced to pop, such as wheat, rice and plain not-popcorn-corn.

Here is some rice being puffed using what appears to be the same process. It's called gun puffing. And here is a forum post describing the same process being used to puff wheat, corn and other grains (if you keep scrolling down you will see more pictures/more description of the process). And another blog post by someone who observed this process in Shanghai and the person was puffing rice. Note that this produces the soft type of puffed grain. When popped over open flame with sand as in India the product has a crispier texture.
Also, interestingly Quaker used to advertise their puffed wheat and rice as "Shot from Guns!".
posted by hecho de la basura at 10:40 AM on June 14, 2008 [2 favorites]

Ah, this will be my unfamiliarity with yer Yankee popcorn :D - what it says is literally "maize kernels" so it is popped corn (I have eaten it myself), but maybe not you popcorn.
posted by Abiezer at 10:43 AM on June 14, 2008

What Americans eat as popcorn is usually a special strain of corn with a tough, waterproof hull. When you cook it, each kernel acts as its own little pressure cooker — the moisture boils but doesn't escape right away, and only after the starch is all cooked does the hull burst and let the pressure out.

Other strains of corn won't pop on their own. I imagine they're still susceptible to the "gun puffing" process that hecho de la basura describes, though, and it looks like that's what your second link is describing.

Does the result still count as popcorn? I dunno. Seems like a matter of definition to me — like "are tomatoes vegetables?" or "is grilled meat barbecue?" If you define "popcorn" as zea mays averta, then no. If you define it as, well, "any popped corn," then yeah, probably. But it seems like a silly thing to argue about.
posted by nebulawindphone at 12:22 PM on June 14, 2008

this stuff is called ポン菓子 pongashi in japanese , the pon represents the exploding sound.
posted by Infernarl at 5:51 PM on June 14, 2008