Articles

By Rabbi Dovid Cohen, Administrative Rabbinic Coordinator

Q. Why would there be a kosher logo on detergent used for washing clothes?

A. If something non-kosher becomes inedible – either because it spoiled or because it was mixed into foul tasting items – the prohibition against eating it falls away.  For that reason, soaps, detergents, and similar items may be used even if they contain non-kosher ingredients.  In fact, the classic and common way to make soap (as contrasted with detergent) is with non-kosher animal fat, and there were Poskim who forbade washing one’s body with such soap based on the principle of sichah k’shtiyah (rubbing food into one’s body is comparable to eating/drinking that food).  The details of that issue are beyond the scope of our discussion, but we can note that most agree that if the soap is inedible, then that concern does not apply.  Even so, there are consumers who choose not to use body soap or soap that will be in contact with their dishes, unless they know that the ingredients are kosher; those consumers would not care about clothing detergent, floor cleaners, or similar items.

So why do we sometimes see a kosher logo on those items?  The somewhat surprising answer is that there are very many consumers who purchase “kosher” items even though they are not Jewish and have no reason to maintain a kosher home.  They look for certified items because of some other benefit that it provides.  For example, they might specifically buy pareve items because they are lactose intolerant, vegan, or have some other cultural or personal reason to avoid meat products.  Those same consumers want their paper and cleaning products to meet that same standard, and manufacturers turn to kosher certifying agencies to confirm that information for their customers.  Thus, the manufacturers request certification, because they know their customers will trust the kosher logo to indicate that the product meets the standard they care about.

Bearing that in mind, kosher certification of non-food items, like detergent and similar chemicals, is treated somewhat differently than the food items that they certify.  The certifying agency faithfully ensures that the inedible item meets the standard that the customers are expecting, without going through the same steps as would be required to certify pretzels, cookies, or some other food item.

One lesser-known halacha that applies in some cases is that Shulchan Aruch (OC 154:12 and Rema YD 1042) says that if a food item becomes “disgusting” one should not use it for a mitzvah, because doing so is not respectful of the mitzvah.  It is as if the person is saying, “I can no longer eat this, so I’ll use it for the mitzvah” which implies the mitzvah is an afterthought and performed with leftovers.  For example, if there is cooking oil that went rancid, a person should not use that for lighting Shabbos or Chanukah candles (and hashgachos should not certify such items).

This article first appeared in the Let’s Talk Kashrus column, Yated Ne’eman, January 10, 2025.