When you need something unique, think a hash: 
#!/usr/bin/perl
use warnings;
use strict;
use feature qw(say);

my %hash;

push(@{$hash{Lemon}}, 'Juice');
push(@{$hash{Lemon}}, 'Cake');
push(@{$hash{Lemon}}, 'Juice');
push(@{$hash{Lemon}}, 'Cake');

my %uniq;
undef @uniq{@{$hash{Lemon}}};
say for keys %uniq;

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Do you really need the array? If not, you can use HoH instead of HoA: 

undef $hash{Orange}{Cake};
undef $hash{Orange}{Juice};
undef $hash{Orange}{Cake};
undef $hash{Orange}{Juice};
say for keys %{ $hash{Orange} };

[download]
لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Unique key/value pair in Multiple key values pair in Hash by choroba
in thread Unique key/value pair in Multiple key values pair in Hash by Seek_Knowledge

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