Although we have explained in the previous Halacha that Pesach food items must have special Kosher for Passover supervision to ensure it does not contain or has not come in contact with Chametz, nevertheless, there are certain products which do not require special Passover supervision.
Fruits and Vegetables
Fresh fruits and vegetables do not require special supervision for Pesach. It is likewise permissible to purchase fresh produce for Pesach use from non-Jews. If there is any concern for Chametz cross-contamination, such as if the crates of fruits are stored next to Chametz baked goods, the fruits should be washed well before Pesach and there is no longer any concern. (Some say must one wash them well with soap and water. During Pesach, one must for sure do this. See Yalkut Yosef, Chapter 447.) In general, however, there is no such concern for crumbs being mixed in fruits and vegetables.
Honey and Oil
Many years ago, Maran Rabbeinu Ovadia Yosef zt”l published a list of precisely which food items one may purchase without specific Passover supervision. (He published this list in his Kol Sinai.) Many other great Poskim concurred. Nowadays though, some say that one should not purchase any food product without reliable Passover supervision. Hagaon Harav Yosef Shalom Elyashiv zt”l was extremely stringent regarding this issue, even with regards to such items as honey and oil, because there are many imitations on the market in additions to the many ingredients and preservatives that are added to these products which require superior Kashrut supervision.
It is for the above reason that we are careful throughout the year to purchase only products that are under reliable Kashrut supervision (even sugar and salt have Kashrut symbols on them). Nevertheless, if there is a specific item that one knows for certain is all natural and contains no additives, such as if one gets olive oil from a friend who has an olive press and makes small batches of natural olive oil, it does not require a Kosher for Passover symbol. In general, though, one should take care and accustom one’s family to purchase only items that have a reliable Kosher for Passover symbol on them.
Nuts
Any kind of nuts, such as peanuts, walnuts, almonds, and seeds, that are roasted and salted must have a reliable Kosher for Passover symbol, as there can sometimes be some flour added to the mixture. Although there may be a store which claims there is no flour added to the nut mixtures, one should nevertheless not purchase such nuts without adequate supervision in place.
Chicken
It is now customary to purchase chicken products under specific Kosher for Passover supervision as well. The reason for this is because sometimes, a kernel of wheat can remain inside the chicken and when it is cooked, it has the potential to prohibit the entire dish. The above concern was more prevalent in previous generations when chicken would be soaked, salted, and clean at home. Nowadays, however, when these processes are carried out in slaughterhouses, finding a wheat kernel inside one’s chicken is almost unheard of. It is nonetheless customary to feed the chicken food which is Kosher for Passover so that when the chickens are slaughtered, they are completely free of any Chametz concern.
Eggs
The same applies to eggs in that, essentially, they do not require special Kosher for Passover supervision. There is nonetheless a concern that if the coop was not Kosher for Passover, some of the chicken feed may have stuck to the eggs. For this reason, the Ben Ish Hai writes that the eggs should be washed before Pesach under cold water in order to allow they usage on Pesach. This is the proper procedure for countries where eggs are bought from non-Jewish companies. In countries where eggs are stamped, there is no Chametz concern posed by the ink since this ink is not even fit for canine consumption.