JONNY PHILLIPS:

Custard.  It conjures up images of works canteens, hospitals, school dinners and kids parties.  It's definitely one of those foods that you either love or hate, but it's pretty harmless nonetheless.  Or is it?  Could custard have a more explosive side? Is custard a bomb waiting to go off?

[LAUGHS] You didn't really think that was gonna blow up did you?  Fear not, there's absolutely no need to defuse that trifle in your fridge. But what if we apply a bit of science?  What if we use custard powder instead?

Right, lets get rid of this first.  Okay, now I've got this tin, into which I shall place this candle.

Then I get some custard powder and I'm gonna sprinkle it around the candle like that, make sure there's plenty in there.

Okay,  Then I get this rubber hose and poke it into this hole, which I made earlier.  Okay now I'm gonna light the candle. Put the lid on and retire to a safe distance. Now please do not try this at home. Now all I've got to do is blow.

So what just happened? When I blew into the tin, I introduced oxygen - one of the essential ingredients for fire - and at the same time, I turned the pile of custard powder into an airborne dust cloud which created the explosion. But here's the thing, there isn't anything explosive in custard powder, just the act of turning it into a dust cloud and igniting it in a small space made it explosive.

Custard powder was invented in 1837 by pharmacist Alfred Bird.  His wife was allergic to traditional egg custard so he came up with a cornflour based substitute.  But it wasn't until his friends sampled it that he realized its commercial potential and the now famous Birds Custard was born.  And in 1902 this place, the Custard Factory in Digbeth, Birmingham, was established to produce it.

Even back then they knew about the potential danger of custard powder, so instead of the usual open plan layout, the factory consisted of a series of rooms separated by thick walls and corridors sectioned off by these huge steel blast stores, so that any explosion would be contained.

So next time you see that long forgotten tin of custard powder at the back of the kitchen cupboard, just remember what its capable of.

But, don't try this with your custard powder at home