Kosher Dutch Oven

I am looking to purchase a cast iron Dutch oven. Many of them say they are preseasoned. What do I have to do to use them in my kitchen? Is there one brand better than another? Do any of them have a hechsher?

Shalom!

Thank you for your question.

Many of the cast-iron Dutch ovens/skillets are “pre-seasoned” which means that the appliance has been dipped into shortening, or fat, or some other flavoring substance in the course of manufacture.

This applied substance is baked onto the surface of the appliance and protects the appliance from rusting. This is because cast iron differs from all other cookware in that if left untreated it will rust. This coating is indeed a Kashrut concern since these coatings are often animal based. Even if the packaging claims that the coating is vegetable based it cannot be relied upon. This true because even if it is indeed vegetable based it may have been applied on non-Kosher equipment.

As such, such an appliance, even when new, must be kashered prior to its first use  it can be koshered by hagala, immersing it in boiling hot water. (Chazon Ish, YD 44:4). It goes without saying that a used appliance of this nature will need kashering in any event. So too, it will need to be immersed in a mikvah after it is koshered.

It should be noted, that when the coating has been “kashered off” the appliance is unprotected, and therefore, as mentioned, it will rust. One can create a new kosher coating by smearing oil and baking it so that the oil polymer rises and forms a solid layer. The oil should be applied as thinly as possible and heated past the smoking point. It is then cooled and redone multiple times until a strong cooking surface is formed.