#!/usr/bin/perl
use strict;
use warnings;
use 5.010;

my %par = (
    text    => "Tes\x01t",
    zeichen => qr{[e\x01]}x,
);

test(\%par);
say $par{text};

sub test {
    my ($par) = @_;
    $par->{text} =~ s/$par->{zeichen}//;
}