use strict;
use warnings;
use Set::Array;
use Data::Dumper;
my %HoA = (
    'Fruits'  => [ 'Apple',  'Orange', 'Banana',    'Grapes', ],
    'Fruits1' => [ 'Apples', 'Orange', 'pineapple', 'Grapes', ]
);
my $set1 = Set::Array->new(@{$HoA{Fruits1}});
my $set  = Set::Array->new(@{$HoA{Fruits }});

$HoA{difference} = [Set::Array::difference($set1, $set, 0)];

print Dumper(\%HoA);

OUTPUT:
$VAR1 = {
          'Fruits1' => [
                         'Apples',
                         'Orange',
                         'pineapple',
                         'Grapes'
                       ],
          'Fruits' => [
                        'Apple',
                        'Orange',
                        'Banana',
                        'Grapes'
                      ],
          'difference' => [
                            'pineapple',
                            'Apples'
                          ]
        };