Kitniyot and Rice
Hametz is any fermented substance, solid or liquid, that comes from one of the following five grains: wheat, barley, oats, rye and spelt. Kitniyot, legumes, are not considered hametz. However, many Jews, especially Ashkenazi Jews, do not consume kitniyot during Pesah.
In most Sephardic communities, legumes are not forbidden during Pesah. Some Sephardic Jews, though, refrain from eating chickpeas (humus) and certain types of beans. And Sephardic Jews from North Africa (Morocco, Algier, etc.) do not eat rice on Pesah.
Why? No one, Sephardim or Ashkenazim, considers rice as actual hametz. The reason these Sephardic Jews abstain from rice is because many years ago it was very common to find grains of wheat mixed in the bags of rice. The fields where rice was grown were usually nearby or within the same fields where wheat was grown. To make things more complicated, whole-rice grains and whole-wheat grains look alike. Therefore, it wasn’t unthinkable that grains of wheat might have accidentally mixed within the rice. As we will later explain, the prohibition of hametz during Pesah is so severe that even one grain of wheat could render a whole food as forbidden for Pesah.
In Sephardic communities of Middle East (Syria, Egypt, Iran) the rabbis permitted the consumption of rice during Pesah. To avoid the possibility of accidental presence of wheat in rice, they indicated to check the rice very carefully, three times before Pesah. Brown rice can also be used for Sephardim on Pesah. Enriched rice is problematic because it might contain hametz elements (yeast, wheat starch, grain-based vitamins, etc.).
Following the Ashkenazi tradition, any food to be consumed during Pesah, even foods that do not contain a hametz ingredient, must be prepared or manufactured under special rabbinical supervision. Why? In other areas of kashrut, it takes normally a proportion of 1.6% (roughly 1/60) or higher of a non-kosher element (usually additives) to render the whole product non-kosher. For example: a marmalade that contains a non-kosher element in a proportion higher than 1.6% is not kosher. But, if the presence of that element is less than 1.6% of the whole product, then the product is kosher.
On Pesah, however, the rules are stricter. Even the smallest amount of hametz is enough to render the whole food prohibited. Both Sephardim and Ashkenazim agree that the presence of a non-hametz ingredient in a food renders the whole product unfit for Pesah consumption, even if the proportion of that ingredient is as small as 0.001% of the total product.
Sephardic tradition holds, however, that if a hametz ingredient is mixed, accidentally or deliberately, into that food-product before Pesah begins, it will only render the final product as unfit for Pesah if that hametz ingredient is present in a proportion of or above 1.6%. In other words, if a food made before Pesah contains a hametz element which is less than 1.6% of the total, that food will be kosher for Pesah. Why? Because before Pesah, we apply the standard kashrut laws of 1.6%, and not the Pesah laws of 0.001%. And once a hametz element smaller than 1.6% is considered neutralized, it never “revives” again. According to the Ashkenazi tradition, however, if a 0.001% hametz element is present, it renders the whole food-product non-suitable for Pesah, regardless of when the food was prepared.
I want to explain this in practical terms:
Usually, in the food industry, an element found in a proportion of 1.6% or higher is one of the ingredients of that food-product, most probably an additive.
On the other hand, an element present in a proportion of 0.001% is probably a consequence of an accident or a cross-contamination. Outside kashrut, the presence of a 0.001% element might probably be the case of an allergen, like peanuts-residue, gluten, etc. Therefore, while identify the presence of a 1.6% ingredient is relatively easy, making sure that a 0.001% element is not present is virtually impossible – unless we completely clean and sterilize the factory, restrict the access of any unauthorized person or product; in other words, we make a special kosher for Passover supervision. In that case, the whole area where the food is produced, the machinery, etc., must be sterilized, and a supervisor should be present in the premises to avoid any accidental access of a hametz element, etc. Following the 0.001% rule, any food to be consumed during Pesah, even foods that do not contain a hametz ingredient, must be prepared or manufactured under special rabbinical supervision.