Answer by Rabbi Chaim Hillel Raskin – Rov in Kfar Chabad Beis, Israel:
Chazal prohibited eating matza on erev Pesach (from dawn) prior to fulfilling the mitzva at the seder. (A later custom is to refrain from eating matza for thirty days before Pesach.)
The prohibition applies only to matza with which one can fulfill the mitzva, and not to “flavored” matza (matza ashira) with an altered taste (e.g. egg matza) since it is not kosher for the mitzva. (Such matza is generally avoided out of chometz concerns, though it may be eaten on the morning of erev Pesach.) This restriction applies to children who are old enough to understand the story of yetzias mitzrayim.
From the beginning of the tenth halachic hour (i.e. 3:00 pm, if sunrise and sunset are at 6:00), matza ashira (“hamotzi”) may not be eaten so that the matza by the seder will be eaten with an appetite.
Likewise, wine in either a small or large amount can also satiate and may not be drunk from this time. An in-between amount of wine whets the appetite and is permitted, but since we’re not sure how to measure this amount, we don’t drink any amount of wine from the tenth hour.
In addition, if one knows that even other foods will deprive his appetite for the matza, he should refrain from these foods as well.
On the first day of yom tov, one should wash for the meal before the tenth hour, but it may continue past this time. One should still ensure that one has an appetite by the evening.
It is customary to refrain from eating maror (lettuce, horseradish) on both erev Pesach and the first day of Pesach so that one will eat it at each seder with a fresh excitement for the mitzva.
Though the Alter Rebbe rules that charoses doesn’t require an appetite since there is no special mitzva to eat it and savor its taste (it is only to accompany the maror), the Chabad custom is to refrain from eating the charoses ingredients (apples, pears and walnuts) as well.
However, wine isn’t an integral part of the charoses (it is only added to soften it), and it is therefore permitted (before the tenth hour on erev Pesach).
Chabad custom is to refrain from eating these foods even during the meal of the first seder so that one will retain excitement for the mitzva at the second seder.
The vegetables used for karpas (onion and potato), as well as the zecher l’chagiga (egg), may be eaten on erev Pesach.
Published by The Weekly Farbrengen, a newsletter by Markaz Anash. See Sources
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