You don't need the intermediary @group there, you can do the whole shebang in one go:

use warnings;
use strict;

my @array1 = ("one", "two", "three", "four", "five");
my @array2 = ("banana", "pear", "apple");

my %hash = (
    numbers => \@array1,
    fruit => \@array2
);

for my $group (keys %hash){
    my $statement = join ', ', @{ $hash{$group} };
    print "$statement\n";
}
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Output:

one, two, three, four, five
banana, pear, apple
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