Chapter 80:15
Some Activities Forbidden on Shabbos
15. If one has a mixture of food and undesired material (1), one may remove
the food from the undesired material, but not the undesired material from
the food (2). Even the food may not be removed using a utensil, but only by
hand (3). Furthermore, one may separate only food that one desires to
partake of immediately (4).
Even when one desires to select something to eat out of a [mixture of
different] foods, one must be very careful only to select what one wants to
eat at that moment (or for the upcoming meal), and not to remove food from
the mixture and put it aside for later; only what one desires to partake of
immediately is defined as food in terms of this prohibition, whereas what
one desires to partake of later is considered to be the equivalent of
"undesired material" [at present].
Similarly, it is forbidden to peel onions or garlic and put them aside, for
this is considered to be a prohibited separation. One may peel only what
one intends to use immediately (5).
The outer shell of a garlic head that covers all of its segments may not be
removed, even if one intends to eat the garlic immediately, because it is
considered to be a violation of the prohibition called "Mefarek", which is
a derivative ("Toldah") of [the prohibited "Av Melacha" called] "Dosh" (6).
FOOTNOTES:
(1) The way in which we determine what activities are prohibited on Shabbos
requires some background. Only a handful of the 39 categories of prohibited
activity on Shabbos are mentioned explicitly in the Torah. The Torah simply
states: " The seventh day is Shabbos...don't do any "Melacha" " (Exodus
20:10). It is left up to the Oral Law, taught by G-d to Moses on Mount
Sinai, to define precisely what activities are called "Melacha" and hence
prohibited on Shabbos. The Oral Law (Mishna, Shabbos 7:2) lists 39
activities which are defined as "Melacha"; each of these 39 is called an
"Av," which in its broadest sense means "prototype." Any activity which is
similar to one of these 39 prototype activities, is called a "Toldah"
("derivative") and is also considered to be a "Melacha" prohibited by the
Torah.
The first eleven of the thirty-nine Melachos listed by the Mishna are all
steps in the process of making bread, from ploughing and planting right
through to kneading the flour and baking the dough. The seventh Melacha in
the process is called "Borer" (selecting), and entails removing the waste
products (pebbles, etc.) from the pile of harvested grain. Thus, any
activity which involves removing something undesirable from something
desirable would be considered a Toldah (derivative) of Borer, and
prohibited. In fact, the prohibition includes both sorting an entire
mixture into its individual components and removing a single item from a
mixture. There are many criteria involved which determine whether a
particular activity is included in this prohibition or not, and going into
all the details would be way beyond the scope of Halacha-Yomi. I will raise
some of the general questions involved, but for the practical Halacha in
each individual case, please consult a detailed book of the laws of Shabbos
or your local Rabbi.
(2) The prohibition involves not only a mixture of food and waste, but also
a mixture of two different types of food, one of which is desired at that
moment, the other not. Even sorting a mixture of non-food items with
different functions, such as cutlery, is included in the prohibition. In
addition, even items which are not actually mixed, but merely attached or
piled on one another, are also considered "mixtures" in terms of the
prohibition of "Borer."
(3) Use of a utensil is only forbidden when it makes the actual process of
separating food from waste more efficient, for example, a strainer, an
apple corer or a vegetable peeler. However, using a utensil so as to avoid
soiling one's hand, or to enable one to reach an item that can't be reached
with one's hands, is permissible. For example, one may remove the fish from
the bone with a fork, or peel an apple with a knife (because it is
difficult with one's hands).
(4) "Immediately" includes the time period normally used to prepare for a
meal. For example, if a person usually begins preparing for Shabbos lunch
three hours before the meal, sorting may be performed (with the required
criteria) on food needed for the meal, at any time during that three hour
period. Thus, in order to remove an act from within the framework of the
prohibition, one must take the food (or desired item) from the waste (or
undesired item), with one's hand (or an extension of the hand, like a
fork), for immediate use (or the upcoming meal); an act incorporating these
criteria is defined as the natural eating process, and is not similar to
the prototype activity of Borer, listed by the Mishna.
(5) When it comes to peeling vegetables or fruits, removing the waste from
the food is permissible, because removing the food from the waste is
impossible; peeling fruits and vegetables is not considered an act of Borer
but rather the regular way one eats.
(6) Another of the 39 Melachos listed by the Mishna is "Dosh" (threshing),
that is, the process of removing grain from its husk. Peeling the outer
shell off a garlic is similar to threshing, in that it involves removing
the garlic from its natural container, and therefore it is considered to be
a "Toldah" of "Dosh" (derivative of threshing) and prohibited on Shabbos.
The question is: why is peeling the outer shell of a garlic prohibited even
if its for immediate use, whereas peeling the inner shells is permitted for
immediate use. The answer is that the outer shell is considered the
"container" and thus peeling it is a Toldah of Dosh, for which the leniency
of "immediate use" does not apply. The inner shells are not viewed as
containers, but rather waste products attached to the garlic; therefore,
peeling these inner shells is considered a violation of Borer to which the
leniency of immediate use is applied.