Is one required to immerse a new can opener before using it? As a metal utensil used in food preparation, it might appear, at first glance, that a new can opener acquired from a gentile requires immersion.
In truth, however, it is clear from the Poskim that can openers do not require Tebila (immersion). A can opener does not come in contact with the food, and is used only to prepare the utensil in which the food is stored. Can openers are thus no different in this regard from a hammer or screwdriver, tools which quite obviously do not require Tebila.
What is the status of a nutcracker with regard to Tebilat Kelim?
Seemingly, since a nutcracker does not come in contact with the edible part of the nut, but simply removes the shell, it should not require immersion. However, there is a view among the authorities that any utensil used for preparing food for consumption requires immersion, regardless of whether it comes in contact with the food, and according to this view one would be required to immerse a nutcracker. As for the final Halacha, Hacham Ovadia Yosef rules in his Halichot Olam (vol. 7, p. 267) that strictly speaking, nutcrackers do not require Tebila, but it is preferable to immerse them without a Beracha, in order to satisfy all opinions.
Hacham Ovadia further notes that dentures prepared by a non-Jewish dentist do not have to be immersed before use, even though they are used for eating, because they are made from enamel, a material that does not require Tebila.
Summary: Can openers do not require Tebila before use. Nutcrackers do not, strictly speaking, require Tebila, but they should preferably be immersed without a Beracha. Dentures do not require Tebila.
