Rabbi Zvi Anshel HaLevi Leshem
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1. Some of the oils designated as "kitniot" or "only for those who eat kitniot" are permissible also to Ashkenazim (even according to the position which prohibits kitniot oil), such as peanut, soy, canola and cottonseed oils.
2. Some of the products that are labeled "for those who eat kitniot only" are permissible according to all opinions, since the ratio of kitniot ingredients is less than 50%, and they are therefore annulled in the majority of non-kitniot ingredients. Additionally the kitniot ingredients are often oils such as soybean, that were never included in the prohibition, or derivatives of these oils. Only those foods in which the kitniot ingredients constitute the majority are prohibited. Therefore, many dairy products, "kosher for Pesach" cookies, chocolates and more, which are labeled "kitniot" or "only for those who eat kitniot" or "for those who eat liftit" (liftit and lecithin are both types of canola) are completely permissible for Ashkenazim.
3.Quinoa, which is a very new food (other than for native South Americans), is permissible.
4. There is no problem for an Ashkenazi to be a guest of a Sephardi on Pesach and to eat food prepared in vessels that were used to cook kitniot, even within 24 hours of the meal. This is true since if the kitniot themselves can be annulled in a mixture of a majority of other ingredients, their taste is certainly annulled. Moreover, even if the food contains a kitniot ingredient, as long as it is not the majority and is not recognizable as a separate element of the dish, it is also permitted.
5. Those people who have thus far been careful not to purchase any food item labeled "for those who eat kitniot only", because they believed that this was in fact the Halacha, are not considered to have accepted this as their custom; it is at best a "mistaken custom" and they are not required to perform "vow annulment" in order to eat such items.
6. It is a mitzva to publicize this decision, which is based upon the traditional Halachic methodology of the great authorities throughout the generations, and not upon looking for unnecessary stringencies.