Sharpening Made Easy
Knife Sharpening Information and Equipment
Star-K Kosher Certification
Is there a kashrus issue in taking knives to be sharpened to a sharpener,
knowing that the sharpener also sharpens non kosher knives? In our
experience, the knife sharpeners are constantly bathed in water so they do
not get hot. Therefore, as long as the sharpener is clean, it is permitted
to sharpen on a sharpener that is also used for non-kosher knives. (Butchers
sometimes subscribe to a knife-sharpening service. The butcher must ensure
he is getting back his own knives after sharpening.)
Can one use the same knife sharpener for meat and dairy knives? If the
sharpener gets hot (more than 120F) during sharpening, one should use
separate sharpeners. If the sharpener does not get hot, then one can use the
same one for meat and dairy. The knife should be washed in cool water before
and after sharpening and the sharpener should be rinsed in cool water after
Copyright © 2009 Star-K Kosher Certification
A Summary of the Laws of Tevilas Keilim
One who acquires food utensils from a non-Jew must immerse the utensils in a
kosher mikveh prior to use. One may not use a vessel even once unless
tevilah has been performed. However, food prepared in vessels that had no
proper tevilah, is nevertheless kosher.
a) Only vessels made of gold, silver, iron, steel, copper, tin, brass, lead,
glass, pyrex, corelle and crystal require tevilah with a b’rachah. Unglazed
earthenware, wood, rubber and plastic utensils require no tevilah.
Corningware, porcelain (china), enameled pots, teflon coated pans and
aluminum vessels require tevilah without a b’rachah. Disposable aluminum
pans require no tevilah.
b) A utensil made of a material requiring tevilah should be immersed
inclusive of any plastic or wooden parts attached to it. A utensil made of
wood or plastic requires tevilah if any metal is attached to it, providing
that the metal touches the food and is vital for the utensil’s use. A
utensil made of separable parts requires tevilah only for its metal parts.
c) Tevilah is required only for those utensils used for eating, drinking or
the preparation of food. Only those utensils which come into direct contact
with the food require tevilah. One who purchases a food utensil for a non
food related use (e.g., a knife purchased for cutting cardboard) need not
immerse it. However, it should not be used, even temporarily, for food use.
d) Those utensils that do not prepare the food for its final edible state
(e.g., a kneading hook) require tevilah without a b’rachah.
e) Vessels that are used merely for storage should be immersed without a
f) One may purchase and eat food or drinks directly from their jars or
bottles. Once the jar is emptied of its contents, some poskim permit reuse
of a glass jar for other foods without tevilah. A metal container, however,
should not be reused without tevilah. Some poskim permit reuse of a tin can
that was opened by a Jew.
g) Electrical appliances that come into direct contact with food require
tevilah. An appliance that cannot be immersed in a mikveh should not be
purchased. Thus, an electric urn requires immersion in a mikveh. It is
impossible to do a proper tevilah on an urn unless it is completely immersed
in the water. A Rov should be consulted as to the proper method of tevilah.
h) Only utensils that belonged to a non-Jew require tevilah. These include:
utensils manufactured by a non-Jewish company (even if partly owned by
Jews), those manufactured by a Jewish company but sold in a non-Jewish store
or even those sold in a Jewish store, if they had been purchased from a
non-Jewish wholesaler. If there is sufficient reason to suspect that the
utensils never belonged to a non-Jew, tevilah should be done without a
i) Only those utensils owned by a Jew require tevilah. One who borrows a
vessel from a non-Jew (when no kashrus problems apply) may use it without
j) One who wishes to eat in the home of a Jew who has not immersed his
dishes should consult a Rov.
k) During tevilah the utensil must be clean and free from any foreign
object. Therefore any rust, dirt or labels must be removed prior to tevilah.
When removing labels, one must be sure to remove all glue as well. Stubborn
stickers or glue can be removed with nail polish remover or by spraying with
WD 40 silicone spray.
l) One should not permit a minor (a boy below the age of 13 or a girl below
the age of 12) to perform tevilah unless supervised by an adult. A minor
doing tevilah with adult supervision recites the b’rachah as well. One
should preferably not allow a non-Jew to perform tevilah even when
supervised by a Jew.
m) Tevilah should be done only in a kosher mikveh (some men’s mikvaos are
not kosher for tevilas keilim). If a store has its own mikveh, one must
inquire whether it is under the supervision of a competent rov. One may do
tevilas keilim in the ocean as well. One who wishes to immerse utensils in a
lake should consult a Rov.
n) Before grasping the vessel to be immersed, one should wet one’s hands in
the mikveh. One recites the b’rachah and immerses the vessel without
grasping the vessel too tightly. Better yet, one should first grasp the
vessel with one hand and transfer it to the other hand while the vessel is
under water. One may immerse the vessel in a basket, but dishes should not
be piled one atop another so as not to obstruct the water from reaching all
surfaces of the dishes.
o) Utensils made of separable parts (e.g., a meat grinder or thermos bottle)
should preferably be immersed in an assembled manner.
A List of Materials
Aluminum tevilah no b’rachah
Bone china tevilah no b’rachah
Earthenware (unglazed) no tevilah
Stainless Steel tevilah b’rachah
Stoneware (glazed) tevilah no b’rachah
Rubber no tevilah
© Copyright 2011 Scharf Associates
Copyright 1996 - 2021 by Steve Bottorff