I was recently asked an interesting question. We strive to use two complete loaves of bread for each of the three Seudos on Shabbos. It is not uncommon, especially for those fortunate enough to have homemade Challa, that the loaves may be heavy and sag somewhat. Does this impinge on their status as “whole”?
I did not find any Sefer that directly addresses this issue, but here are my thoughts on the matter.
A little background. While it is always preferable to make a Beracha on a complete item, it is especially critical to the Mitzva of Lechem Mishna for Shabbos and Yom Tov to use a whole loaf of bread. Therefore, while during the week one should make an incision in the loaf before the Beracha, to indicate the location he intends to slice, on Shabbos this should be minimized (whether this Halacha applies at all to our Challos today is a separate issue). Even on a weekday, the maximum permissible incision to preserve the “whole” status of the loaf requires one to be capable of lifting the entire bread when gripping the prospective piece. This would seem to indicate that our sagging loaves may not be considered “complete”.
The question is, is this a general rule that an object is incomplete if any section of it is incapable of supporting the weight of the entire item?
I would tend to be inclined that it is not. I suspect that this Halacha is specific to a situation where a break or separation has commenced, and it merely quantifies the maximum size considered attached. However, when the loaf is intact but merely weak, that infirmity does not deny it from wholeness.