For the printing you should use the qq{} operator. See perlop for details. You could then write you code as:    print qq{DATE\t "$1-$2-$3"\n};

When I ran your program I got the "Expected" ouput rather than the "REAL" output. Perhaps your data source was different.

Just a few comments:

It would be better to use \d and \w in the date matching regex.
It would be better to use a negated character class to match the Inron/Exon data.
On the main loop it is better to use while instead of foreach
Braces don't have to be escaped in a quoted string.

I would rewrite the main block of your code something like this:

while (<INFO1>) {
    if (/^DATE\s*(\d+)-(\w+)-(\d+)/) {
        print qq{\nDATE\t"$1-$2-$3"\n};
    }
    elsif (/\s*\/intron="([^"]+)/) {
        foreach my $item (split('\;',$1)) {
            print "Intron\t{Translation%$item}\n";
        }
    }
    elsif (/\s*\/exon="([^"]+)/) {
        foreach my $item (split('\;',$1)) {
            print "Exon\t{Translation%$item}\n";
        }
    }
}
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--
John.