Machine Matzos: Timing is Everything!

Reviewed March 2024

Meticulous, scrupulous and passionate are terms that describe the fervor, zeal and seriousness displayed by the kosher consumer regarding Pesach kashrus in general, and Pesach matzos in particular.  The kosher consumer has become more sophisticated and savvy with each passing year. Kosher consumers are willing to pay top dollar for a quality kosher product. Pesach matzohs are no exception. Machine matzos with fine mehadrin hechsherim are readily available on the supermarket shelf.  Are all machine matzos created equal?

Regarding matzah baking and the time parameters for chimutz, leavening, the Shulchan Aruch1states, “One should not leave the dough dormant, not for a moment.” If the dough is constantly being worked the chimutz process is impeded.However, the Shulchan Aruch continues, “If the dough is left dormant for a ‘mil’, the dough will rise and will become chometz.”

How long is a ‘mil’?2 The Bais Yosef posits that a mil is 18 minutes.  18 minutes has been the accepted chimutz standard for time immemorial.  After 18 minutes, the dormant dough becomes chometz.  However, not all halachic opinions agree with the 18 minute mil. The Gra, Mogen Avrom3 and others maintain that a mil is 22.5 minutes. Although conventional wisdom, belief and advertisement have indicated that all the mehadrin machine matzos are “18 minute matzos”, are all 18 minute machine matzos created equal?

When a hand matzah bakery claims that their matzos are “18 minute matzos“, from which moment are the 18 minutes measured?  In a U.S. hand matzah bakery, such as Tzelem Pupa, the 18-minute segments are measured from the time the water is poured onto the flour to knead the mixture into dough until the last matzah reaches the oven. From the time that the flour and water are mixed, the matzah baking team has 18 minutes to knead, roll, perforate and bake the matzos. After 18 minutes, the entire operation stops and the cleaning process begins. When this is finished, the next 18 minute segment commences. 

This is not the case with machine matzos. In regular machine matzah production, matzos continue to be produced all day long with intermittent cleaning a few times a day; the machines do not stop. Mixing bowls in nonmehadrin bakeries are cleaned every 18 minutes.  

matzoh illustration

This is not the case with mehadrin machine matzos.  Most mehadrin machine matzos come from Eretz Yisroel.  ‘Mehadrin’ machine matzah bakeries stop and clean after every segment.  However, they utilize both time estimations of a mil for their matzah production. Matzah baking can be broken down into three parts:  kneading, rolling and baking, which overlap one another (see chart). It takes approximately 1 ½ minutes for the first kneaded dough to reach the roller, and an additional 2 ½ minutes of rolling and sheeting for the first matzah to reach the oven. In total, it takes approximately 4 minutes for the first matzah to reach the oven, and 30 seconds for the matzah to be baked. In a machine matzah production, the matzos are continuously kneaded, rolled and baked for an entire 22.5 minute segment – the Gra’s estimation of a mil. However, each part of the 22.5 minute segment concludes within 18 minutes, allowing enough time for the last matzos to be rolled and baked within 22.5 minutes (see chart).

In these bakeries, the first 4 minutes of kneading are not calculated in the “18-minute count” because the halachah states that chimutz (leavening) does not begin if the dough is constantly being worked. This is what is happening during the kneading and rolling processes; therefore, the 18 minute segment begins when the initial matzah starts baking. The entire segment takes 22.5 minutes, which is in compliance with the 22.5 minute mil.  However, each part of the segment lasts no longer than 18 minutes; hence, the bakeries call their matzos “18-minute matzos”. This holds true for both regular (peshutos) and shmura mehadrin machine matzos. The only 18 minute machine matzos that are calculated from the time the flour and water are mixed, as is done in hand matzah bakeries, are chabura matzos.

What are chabura matzos?  Many matzah bakeries allow chaburos, individual groups, to rent time in a bakery to bake their own matzohs.  When chaburos bake matzos, they start calculating the 18 minutes from the time that the flour and water are mixed.  Their clean up time is longer than the regular non-chabura productions. Typically, a machine matzah clean-up takes 10 minutes between segments; a chabura clean-up can take up to 45 minutes.  When machine matzos (such as Hadar, B’tam, Jerusalem or Yehuda) advertise on the box “18-minute matzos” they are using the 22.5 minute standard (unless the box states “chabura 18 minute matzos” or Chabura brand 18-minute machine matzos), indicating that it is an 18 minute segment from start to finish.

All of the mehadrin machine matzah bakeries possess very reliable kosher supervision.  However, the kosher consumer should realize that not all mehadrin machine matzos are created equal.

1. Orach Chaim 459:2.

2. O.C. 459:2; Mishnah Brurah 15.

3. O.C. 459:2; Biur Halacha ibid.