What you're trying to do is use "symbolic references" (a.k.a. "soft references"); you can do it like this:

#!/usr/bin/perl -w

use strict;

no strict qw(refs);

our @menu_info=qw(1 2 3);
our @menu_sell=qw(3 4 5);

foreach my $foo ("info","sell") {
    print "Values in \@menu_$foo: ";
    print join ",",@{"menu_$foo"};
    print "\n";
}
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The problems are that symbolic references only work with global variables (because they have to be in the symbol table), and they're prone to errors. If you typed @{"Menu_$foo"}, you could be wondering for a long time why you get an empty array back.

That's why "use strict;" disallows them.

You're much better off using the hard reference approach, which is what the answers above this one recommend.
--
Mike