use strict;
use Data::Dumper;

open (FOOD, "<", "food.txt") or die "Can't open food.txt: $^E";
my %categories;
while (<FOOD>) {
    chomp;
    my ($category, $item) = split(/\s+/);
    push(@{$categories{$category}}, $item);
}
print ">$_<\n",Dumper($categories{$_}) for keys %categories;
close FOOD;