Like a saltine stripped of all its luxuries, Passover matzo is made only of flour and water: no shortening, no salt and especially no yeast.
It sounds simple. It isn't.
Consider that the Passover matzo maker has just 18 minutes--not a minute more--to complete the process of making the unleavened bread from start to finish. That figure is the result of rabbinical calculations recorded in the Shulchan Aruch, the primary compilation of rabbinical law, which says the process of leavening begins in the time it takes to walk a Roman mile.
To determine just how long it takes to walk a Roman mile, several designated walkers were gathered for a rabbinical experiment long ago, a holy race of sorts. The person who walked the distance the fastest made it in 18 minutes. That became the time limit for matzo makers.
It might help to know that a Roman mile is 2,000 cubits. And what's a cubit? (Sorry, Mr. Cosby.) A cubit is the length of the forearm from elbow to fingertips or half the length of a pace (a mile was 1,000 paces, mille passuum, and hence 2,000 cubits). And you thought the metric system was confusing.
Beyond the time limit, the flour used for Passover matzo must be monitored by a rabbinical authority from the time it is ground to be sure that it doesn't come into contact with water. If even a little water touches the flour, fermentation could begin too early.
In addition, the Passover matzo maker must keep the environmental conditions of the bakery under tight control. With this in mind, certain provisions were laid out in the Shulchan Aruch to prevent any leavening during the production of matzo. These measures are illustrated in the steps taken at Yehuda Fishkind's Baltimore Matzo Bakery, which produces shmura matzos, the most rabbinically correct matzos there are. Fishkind's bakery is one of just eight bakeries in the country that produce handmade shmura matzos; considering the rules, it's no wonder there aren't more.
If flour is destined for shmura (watched or guarded) matzo, the grain must be monitored by a rabbinical authority not just from the time it is milled but from the time it is harvested. This means Fishkind has to pick the grain for his matzo at just the right time. If harvested too soon, the grain will not be ripe. And if the grain is allowed to mature too long on the plant, it will crack and begin to sprout, meaning it would be a little too eager to ferment--great for making beer but too far gone for matzo.
When the best grain is selected and the harvesting window is determined, the reaping begins. Then the shmuring really begins. The wheat has to be constantly watched and protected from moisture. Getting the kernels of wheat off the plant is just the first step. Fishkind tells of his first year in business, when the harvest was on Sunday but the grain could not be packed until the next day.
"Since the grain could not be locked up for the night," Fishkind says, "I stayed with the grain [in the field] to make sure it wasn't tampered with." The first year's batch was truly guarded matzos.
Next the grain is sifted and packed in waterproof sacks and stored until it is ready to be ground. When the grain finally is ground, special milling procedures have to be followed to minimize the heat of grinding. Most flour is moistened to keep it cool during milling, but Passover flour must not be moistened before the dough is mixed. Instead, the process is slowed way down to allow any heat generated by grinding to dissipate without harming the grain. As an extra precaution, Baltimore Matzo Bakery has a stone mill; stone is a poor heat conductor, so the grinding imparts as little heat as possible.
There are still more leavening prevention measures outlined in the rabbinical code. No windows are allowed in the bakery or grain storage areas because heat from the sun's rays could taint the flour and dough. And the water used to make the matzo must be cooled overnight to disperse residual heat. Since the Shulchan Aruch was written before the development of insulation, no provisions for it is made in bakery construction, but amendments may be forthcoming.
Finally, after all these precautions, the matzo may be made--with the full 18 minutes still on the clock.
So it begins at the Baltimore Matzo Bakery, with a specially built hearth oven, a well-sanitized work space, a well-trained staff and some of the most closely watched flour in the world.
First the bakers add the water, adjusting the amount depending on the percentage of moisture in the flour and the humidity in the air. And since there are prohibitions against adding flour after the first water has been added, the liquid has to be added gradually. With no adjustments allowed, these guys are working without a net.