Double Dipping Causes Disease

All you double-dippers, back away from the chip dip bowl!

Seems the famous Seinfeld episode was right - double-dipping does transfer mouth microbes from bitten chips or vegetables into the dip. After multiple double-dippers, what might look like an enticing snack may actually be a microbial soup, a new study suggests.

The research, by food science students at Clemson University in Clemson, S.C., found that for every time a bitten cracker went back into the bowl, hundreds, even thousands of bacterial cells went in with it.

Profession Paul Dawson, the food sciences professor who oversaw the project warned: "It could be a big party. You have a lot of people dipping. So every time someone dips they're inoculating that many cells into the dip."

The average human mouth is teeming with bacteria . . . the fact of the matter is ... if there was somebody in the room had that a contagious disease who was double-dipping, it's a pretty high risk that it's going to be transferred to other people if they're going to be eating out of that bowl," he says. Dawson's students tested dips of different pH levels - a cheese dip, a chocolate dipping sauce and salsa.

"The two factors that affect the amount of bacteria in two words are the consistency of the dip and the acidity of the dip," Dawson notes. Dawson suggests hot dips might provide ideal conditions for microbial growth. And he notes that as a party goes on and the amount of dip in a bowl declines, the microbe content of what remains would be expected to rise.
All this new-found knowledge has made Dawson approach the practice of dipping with a new level of caution: "I probably would avoid the dip bowl. I would pass on that."