Well, i'd choose to put these things in arrays and hashes if i where you, this is a string, where you use :: and || as delimiters.
In this case, it's easy to remove using a regexp, since you allways start with ::

#!/usr/bin/perl
#
use strict;
my $scalar = "::fruits||apple::fruits||orange::vegetable||celery::vege
+table||lettuce";

$scalar =~ s/::vegetable\|\|celery//;

print $scalar;
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Anyway, play with it, and try something like this:

#!/usr/bin/perl
#
use strict;

use Data::Dumper;
my @arr = ( {fruits => "apple"},  
            {fruits => "orange"}, 
            {vegetable => "celery"},
          );

print Dumper(@arr);
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