1. Chametz:
Fermented or leavened wheat, rye, oats, spelt and barley. When these grains come in contact with water, they leaven within 18 minutes. In the case of hot or salted water, leavening takes place instantly.
Chametz may not be consumed either by eating or drinking, and may not be held in one’s possession, nor may any benefit be derived from Chametz. Grain flour is commonly produced from grains that have been washed and tempered. Tempering is the process by which grains are softened by soaking in water, and this flour and all products made with it are, therefore, chametz.
2. Kitniyot:
Leguminous vegetables such as beans, peas, corn and rice. The consumption of these foods is restricted by European Rabbinic tradition, though these foods are not Chametz. Unlike Chametz, benefit from and possession of Kitniot during Passover are permitted. Yemenite, Sephardic and Oriental Jews are not bound to this custom by their traditions. The tradition of the Kitniot restriction has been steadfastly maintained by all Jews of European origin for centuries. This includes the Jews of France, England, Germany, Russia, Poland, Hungary, Austria and the Low Countries.
3. Matzah:
Unleavened bread prepared from the flour of grains that have not been washed or tempered, and have been milled under supervision, completely protected from any contact with water. Matzah may be prepared only with water that has been stored overnight. It is kneaded into dough either by hand or machine, but only in a cool room, since heat may cause instant leavening.
The dough may not be left idle for a period longer than 18 minutes. It is rolled into thin sheets and then baked. All equipment used in the preparation of Matzah must be constantly cleaned of dough crumbs, and the oven in which Matzah is baked must be set at the proper baking temperature.
Insufficiently heated ovens cause leavening to occur.
Once Matzah has been baked properly, leavening can no longer occur, and the product can no longer become Chametz. Therefore, Matzah products such as ground Matzah meal, flour and farfel may be cooked in hot water, baked or blended with any variety of Passover ingredients.
4. Shmurah Matzah or Mitzvah:
Matzah used for the Seder on Passover eve. All Jews must fulfill the mitzvah of Achilath Matzah – eating of Matzah. This Matzah is eaten at the Seder before the Seder meal, at which time the blessings of Hamotzi and Al Achilat Matzah are pronounced. Such Matzah must be prepared with the express purpose of the mitzvah of Matzah LeShem Matzah Mitzvah.
It is traditional that the flour from which this Matzah is prepared should be specially supervised from the time the wheat is cut – Shmurah Mishaath Ketzirah. When this special supervision has been instituted only from the time of milling – Techinah – matzoth prepared from such flour may be used for Matzat Mitzvah only when the traditional Shmurah Mishaath Ketzirah Matzah is not available.
5. “Matzah Ashirah:”
Matzah made from flour kneaded with fruit juice or eggs. This Matzah may not be used for the mitzvah regardless of which flour is used. This type of Matzah is commonly referred to as egg or grape Matzah. Water may not be used in the baking of this Matzah since adding water to the dough would create instant leavenings.
According to European Halachic tradition, such Matzah may be consumed on Pesach only by the elderly, sick or young children who cannot digest regular Matzah.
Under normal circumstances, this Matzah should not be used; both because it is feared that some water may have accidentally been blended into the dough, and in deference to the opinion which maintains that the mixture of flour with any liquid other than water causes immediate chametz.
6. Bedikat Chametz:
The search for Chametz. On the night of the thirteenth of Nisan, a search for Chametz is to be conducted in the home, wherever Chametz may have been brought during the year. The search is conducted in the evening, by candlelight. Chametz found during the search is set aside for burning the next day.
7. Bitul Chametz:
The nullification of Chametz. Since Chametz may not be held in one’s possession during Passover, one may rid oneself of the Chametz by declaring all types of Chametz in one’s possession to be dust and ashes, abandoned property.
The Bitul is pronounced immediately after the search, to nullify the Chametz that may have been overlooked, and again after the burning in the morning, to include any additional Chametz that may have come into one’s possession in the interim.
8. Biur Chametz:
The destruction of Chametz. All Chametz in one’s possession must be destroyed in the morning the day before Passover. For the exact times before which the Chametz must be burnt see Halachic times for Pesach.
The daylight hours of each day are divided into twelve parts; each twelfth is then reckoned as a portion hour of that day. Chametz may be eaten only during the first four portion hours (see the time listing for your area); it may be used or sold during the fifth portion hour. During the sixth portion hour, all Chametz must be destroyed.
However, it is customary to destroy the Chametz in the fifth portion hour to allow for the pronouncement of the Bitul for any Chametz that has been overlooked. It is not permitted to rely solely on the utterance of the Bitul to fulfill the mitzvah of Biur Chametz.
Though any method of complete disposal is permitted, i.e., flushing into sewers or throwing into the sea, it is traditional to destroy Chametz by fire during the fifth portion hour of the day, after which the Bitul is pronounced to nullify any Chametz that may have been overlooked.
The Bitul cannot be pronounced during the sixth portion hour of the day, since at that time, the use of Chametz is restricted and one can no longer rid oneself of its possession.
9. Mechirat Chametz:
Sale of Chametz to a non-Jew. The requirement of Biur Chametz is limited to foods under Jewish ownership and possession. Chametz that has been transferred to a non-Jew need not be destroyed.
Such transfer of Chametz, by legal and binding sale with properly executed contract (Shtar Mechirah) gives the non-Jew full title to all Chametz foods. This transfer is traditionally carried out by engaging the Rabbi to act as an agent, with power of attorney to sell the Chametz to a non-Jew by means of Kabolath Kinyan and contract – Shtar Harshaah.
The Rabbi, acting as an agent for the owners of the Chametz, then enters into an agreement with a non-Jew for the sale of Chametz. When the sale is carried out, a limited amount of Chametz is not sold and set aside to be destroyed on the following day, in order to fulfill the mitzvos of Bedikah, Biur and Bitul.
Chametz that has been sold must be put in a completely sealed-off place, inaccessible during Passover.
10. Chametz SheAvar Alav HaPesach:
Any Chametz held over Passover under Jewish ownership. This Chametz may not be used or sold after Passover, as a penalty for failure to perform the mitzvahs of Bedikah and Biur properly. Selling the Chametz before Passover to a non-Jew avoids Jewish ownership during Passover.
The mitzvah of Bedikah and Biur have therefore not been violated, and the injunction of Chametz SheAvar Alav haPesach is avoided.