(The latest in a series of recent posts which, oddly, are actually related to the title of this blog. This time, I even discuss biur chametz!)
Take a walk through a religious neighborhood of Israel on Passover Eve, just before the start of the festival. Chances are you'll come face to face with substantial quantities of chametz. Bread, rolls, pitot, breakfast cereal, right in the middle of the street.
I'm referring to the smoldering remains of the morning's biur chametz, or burning of the chametz. In better organized locales it will be contained in barrels; elsewhere, it may lie in the middle of a vacant lot.
Let me clarify that no Jewish law is being violated. These remains of leaven have been abandoned ownerless (hefker) in a public area; chances are they have also been doused with lighter fluid to render them inedible. The halachic requirements have been satisfied. Yet still there is something unseemly about walking to shul for Pesach and passing piles of chametz along the way.
The problem arises because chametz is, perhaps surprisingly, difficult to burn.
Try setting fire to a challah roll and you'll see what I mean. The flame, assuming it catches, licks around the edges of the roll, charring the surface. Then, having consumed the available fuel, it goes out. The remainder of the roll is left intact and entirely edible. We might call it toast. Yum!
Fire requires both fuel and oxygen. Thus, it can survive only at the interface between the two - that is, the surface of the chametz. The interior can't burn due to the shortage of oxygen, and the fire can't penetrate to the interior because the charred exterior is no longer viable as fuel.
That's what usually happens when you throw a roll, or pita, or loaf of bread, into the fire for biur chametz. The outside will char, even throughly. But poke it with a poker and you'll find a tasty chametz interior.
A typical solution is to increase the surface area, for example by crumbling the chametz before burning it. Surprisingly, though, this doesn't necessariliy help. A pile of crumbs can be as impenetrable to fire as a solid roll. The outer layer of crumbs is burnt, and the rest remains untouched. Typically, also, many of the crumbs fall beyond the reach of the fire.
To thoroughly burn a pile of crumbs, you generally have to sprinkle the crumbs over a strong fire gradually, allowing each layer to be burnt before adding the next. This can take time, which is usually short on Erev Pesach.
In closing, some practical tips for burning your chametz. Make sure you leave enough time (and kindling) to prepare a strong fire and to gradually crumble your chametz into it. Equip yourself with a poker for tending the fire, and a supply of water for dousing it. You may need lighter fluid for preparing the fire and for drenching the chametz to render it both more flammable and thoroughly inedible.
Most important, take all appropriate safety precautions. Don't start a fire near a lawn or underbrush, or on asphalt. Contain it in a metal barrel if possible. Keep plastic out of the fire; it releases toxic fumes when burnt. Never leave a fire to smolder unattended. Always keep young children at a safe distance.
Have a happy, kosher and safe Passover!