The mishna[1] states: “They brought before him matza, chazeret,[2] charoset, and two cooked foods, even though charoset is not a mitzva. Rabbi Elazar b’Rabbi Tzadok says it is a mitzva.” The gemara[3] inquires what the purpose of charoset is according to each opinion. We will deal with each possibility separately.
If charoset is not a mitzva, we use it because of the concern about “kappa.” There are two main opinions among the Rishonim regarding what kappa is. Rashi says that it is a venom-like liquid that is found in sharp-tasting vegetables, and it is neutralized by the special essence or even the odor of charoset.[4] Rabbeinu Chananel says that it is a dangerous worm that grows on chazeret and is killed by the charoset. Tosafot[5] discusses why only a health hazard is raised and not a halachic one, as it is forbidden to eat worms. One possibility they raise is that this worm is considered a natural part of the vegetable and is not included in the prohibition of eating small creatures. Another possibility is that it is not likely enough that there is kappa for there to be a kashrut problem, but we are stricter regarding the safety concern.
According to the position that charoset is a mitzva, it serves as a remembrance either of the tapuach tree[6] or of the mortar, each of which has historical significance in connection with Bnei Yisrael’s stay in Egypt. Both explanations may actually be correct, as Abaye[7] says that charoset should be sharp to recall the tapuach and thick to recall the mortar.
The classical sources do not mention eating charoset along with the maror but rather dipping the maror into charoset. In his commentary on Mishna,[8] the Rambam claims that according to Rabbi Elazar b’Rabbi Tzadok, one should make a beracha of “al achilat (eating of) charoset,” but he notes that we do not rule that way. In his halachic work,[9] not only does the Rambam not mention the beracha, but he also refers to dipping the charoset, not eating it. In fact, the gemara[10] cautions not to immerse the maror in charoset for too long because the maror might lose its bitter taste. This appears to parallel the fact that we do not eat the matza and maror together earlier in the Seder so that the maror will not diminish the initial taste of the halachically more important matza.[11] The Ran[12] explains that since the maror is only dipped in the charoset, there is no problem of the charoset nullifying its taste the way we are concerned that maror (which requires a substantial amount) would nullify the mitzva of matza. Therefore, it should come as no surprise that the Shulchan Aruch[13] says: “One must shake off the charoset from it [the maror].”
This does not mean that any amount of charoset on the maror endangers the validity of the maror. Tosafot[14] says that since charoset was instituted to be used with the maror, even if only for health reasons, it does not compromise the fulfillment of the mitzva of maror. The Shulchan Aruch also does not instruct us to clean the maror entirely, but rather to shake off the charoset to prevent significant amounts from remaining. Consequently, one should not spoon on charoset, but only dip the maror in it.[15]
In summary, the charoset is not intended for eating, but rather for dipping, and one should not leave significant amounts of it on the maror. If one wants to eat more of the charoset, he should do so later during the meal or on another day of Pesach.