We’ve all done it at one time or another. Some call it double-dipping — scooping a huge corn chip in party dip or salsa, taking a bite and then placing the chip back into the bowl again for another scoop.
Most people frown on the act of double-dipping because they assume it spreads unwanted bacteria into the dip bowl.
MythBusters recently examined the socially blasphemed behavior by testing bacterial growth in petri dishes using sterilized chips and a salsa-like substance.
They concluded double-dipping adds only trace amounts of bacteria to the salsa, and noted most dips already contain bacteria, so double-dipping only adds a few more microbes than the multitude swimming in your salsa to begin with.
On the other hand, Paul L. Dawson, Professor of Food Chemistry at Clemson University, South Carolina, was inspired to conduct dipping experiments after watching a re-run of a 1993 Seinfeld episode.
The episode featured George Castanzo attending a funeral reception where he double-dips and is immediately confronted by his girl friend’s brother.
Professor Dawson’s students used wheat crackers and found that 3 to 6 dips in a bowl transferred 10,000 bacteria from an eater’s mouth to the remaining dip.
In Dawson’s experiments, thick dips were safer with fewer bacteria, and their number decreases over time. But there was a higher bacteria count from chips dipped into a runny salsa because the excess salsa slipped off the chip and returned to the bowl.
Not Worth The Risks
In a 2010 issue of the Canada Free Press, Dr. Gifford Jones warns double-dipping may unwittingly expose festive chip dippers to meningitis because saliva contains germs that can cause meningococcal meningitis.
“It’s a potentially life-threatening infection that infects the covering of the brain and spinal cord.”
Other risks stem from exposure to a variety of viruses such as the influenza virus and the cytomegalovirus (CMV). “The CMV is normally in the respiratory system, but can get into saliva and affect a number of organs.”
And munching from a double-dipping bowl is inherently dangerous for those whose immune systems have been compromised by HIV. Another risk from double-dipping in the communal bowl is mumps and herpes.
Experiments have shown that the herpes virus can remain alive for hours when deposited on a surface by someone with an open herpes sore.
Dr. Jones adds: Double-dipping is like saying to yourself, “Do I want to kiss everyone at this party?” Powerful strains of bacteria and viruses only need limited exposure to cause infections.
Research shows that when a person dunks a chip they’ve taken a bite from back into the common bowl of dip they transfer roughly 10,000 bacteria to the dip.
“Double-dipping is like getting a lick of someone else’s saliva. It spreads bacteria,” said Donna Duberg, a germ expert at Saint Louis University.
Duberg suggests party guests snack from their own packet of chips or boxed food items that have their own individual packets of sauce. Dipping chips in a common dip bowl at parties and gatherings just isn’t worth the risk.