PITTSBURGH – Beware the harmless-looking QR codes on product packaging. Some pack a powerful wallop — or money shot.

The H.J. Heinz Company, known for its ketchup, found its face as red as the ubiquitous condiment when a QR code presented consumers with hardcore porn instead of product information.

A consumer in Germany noticed the problem when he used his phone to scan the code on a ketchup bottle and, without so much as a by-your-leave, found himself on an adult website.

“I happened to scan it during lunch and I was a bit surprised where I got redirected to,” Daniel Korell, the misdirected consumer, told BBC News. “I found it rather funny….”

Korell subsequently posted a note on Heinz’s Facebook page: “Your ketchup is probably not for minors.”

According to Heinz, the misdirection was the product of an expired label. Heinz neglected to pay for a renewal of the QR code, and — like everything else that expires in cyberspace — the code was snapped up by an adult entertainment company hoping to capitalize on existing traffic.

QR codes work much like hyperlinks, except consumers can’t see the URL before they arrive at the site. Instead, they must take it on faith that the site at the other end of the arcane series of numbers and stripes is the place they intended to go.

Unfortunately for Heinz, the stealth-porn gaffe was particularly embarrassing: The QR code was supposed to dump consumers on a special-promotion page, potentially increasing the number of times the code would be scanned.

Heinz apologized for the error and presented Korell with a free bottle of ketchup as a token of its gratitude.