The 2 reasons for dipping bread in salt and why the Chasam Sofer Did Not Eat Salt On Friday Night

1) Al Kol Korboncho Takriv Melach.
The table is like a Mizbeiach and the bread
is like a Korbon which requires salt.

2) Bread (whole wheat) has some harmful

toxins .By adding salt to the bread the harmful
effects are removed.

There is also an Inyan to have salt on

the table while waiting for others to wash.

The Soton is Mekatreg during that time

(no Mitzvohs performed) . The salt at the

table, represents the Bris Melach and

protects from the Kitrug.

On Friday night  it is not applicable

1a) There was no burning of Korbanos
on Friday nights.

2a) Pas Nekia (white flour) doesn't require

salt.

The  protection of the salt from Kitrug,

all it requires, is placing it on the table.

There is no need to eat it.

According to the Chasam Sofer ,On Friday

night,since we eat Challah which is

Pas Nekia (white flour) and Korbanos

were not burnt on Friday night, therefore

there is no need to dip the Challah in salt.