Wine Insurance

Mendel from Givat Moshe asks::

I am having guests who,
unfortunately, do not yet keep Shabbos. I am concerned that they should
not cause the sh’mittah wine I intend to serve to become forbidden.
Would I be permitted to boil up the wine to make it immune to prohibition
through touching?

It is permitted to boil up wine if this makes it tastier for
those who drink it. However, if the sole purpose of boiling the wine is to
prevent it from becoming forbidden through touching, this is prohibited. Since
the end product is not tastier, the reduction in volume through evaporation is
considered destroying sh’mittah produce (Beis Ridvaz 5:6). Wine is
commonly boiled in order to make it immune to prohibition through touching (by
non-Jews, etc.). The method used by wine manufacturers is to pasteurize the wine
in sealed vessels. Since the wine that evaporates as a result of this process
recondenses on the ceiling of the vessel, the problem mentioned above does not
exist. There is no reduction in volume. Additionally, since this is normal
practice in other years, the taste of the wine is not detrimentally affected (Minchas
Shlomo
No.25).

One should be aware that both Rav Shlomo Zalman Auerbach,
zt’l, and Rav Elyashiv are of the opinion that boiling in sealed vessels, which
does not result in a reduction in volume, is not effective in making the wine
immune to touch.