foreach my $row ($ts->rows) {
	@$row = map { clean_text( $_ ) } @$row;
	#...
}

#...
my $cell1=$te->rows->[$rowIndex][1];
clean_text( $cell1 );
#...

sub clean_text {
	# remove all control characters
	$_[0] =~ s/[[:cntrl:]]+//g;
	
	# remove white space at start/end
	$_[0] =~ s/^\s+//;
	$_[0] =~ s/\s+$//;
	
	# or remove all white space
	$_[0] =~ s/\s+//g;
}