What is Chametz?

Question

During Pesach and Chag Matztzoth, there are many beliefs of what needs to be removed during this time, and what chametz actually is. I.e., there’s the removal of just yeast, then there’s the removal of yeast, baking soda, baking powder, soaps, and etc. With that being said, what is chametz according to the letter of the law? Does baking soda and baking powder fall into the category of “chametz?” Also, do soaps, detergents, and cleaners need to be removed along with the yeast?

Answer 1

There is chometz and Seor which both need to be removed. Se'or is loosely translated as yeast, in reality, it is a sourdough starter made from wheat, barley, spelt, and barley (or oat). Yeast these days is not made from the 5 grains, therefore according to the letter of the law need not be removed.

Chometz is flour which has come into contact with liquid and has been dormant for a period of time that allows the food to become chimutz (wheat flour and water under normal circumstances is 18 minutes) before being baked it then becomes chometz.

This is according to the letter of the Law. Obviously, a Rabbi should be consulted about individual minhagim.

Answer 2

According to the strict letter of the law chametz is one of the five grains that has become fermented. See Pesachim 35a. The five grains are traditionally identified as wheat, barley, spelt, rye, and oats, though some of these identifications (especially oats) are somewhat controversial. In theory, other grains (such as rice and millet), pure yeast, chemical compounds (such as baking soda) are not chametz. You can see some more background here. https://en.wikipedia.org/wiki/Chametz. The problem is that, especially in this day and age, many products many contain mixtures of chametz, which is why kosher consumers rely on annual lists of what products do not require kosher supervision for Passover and, for all other products, require kosher certification.

There are also many complicated and subtle details of defining chametz that are relevant to these questions. For example, what if chametz is a minority or trace ingredient? What if the product contains chametz but is no longer "food," such as soap (and how do you define "no longer food")? How do you identify when fermentation has begun? What accelerates or slows the fermentation process? These are all very complicated areas of halakhah and people often take a strict approach to be safe. In addition, the cultural and religious practice has become to add many many stringencies to the prohibition against eating chametz for a variety of reasons. As just one example, most Ashkenazi Jews do not eat kitniyot or legumes, even though they are not chametz. See Mishnah Berurah to 453:6. All of these factors are why you see people throwing out or storing away many products that one would not think contain chametz or in fact do not contain any chametz.