Knock it off already. You think people have noticed the double dipping? They do. And you need to stop. I’m not just saying that because your uptight relative has a huge problem with it. I get it, it’s fun to watch them squirm over this. There are scientific reasons why you need to stop as well as social ones. I have outlined the below. You are welcome.
Who Studied This?
Undergraduates at Clemson University studied double dipping.
How Were The Experiments Conducted?
Bitten crackers and unbitten crackers were studied by students. They measured the amount of bacteria could potentially transfer from the crackers by dipping into a cup of water.
They found “about 1,000 more bacteria per milliliter of water when crackers were bitten before dipping than solutions where unbitten crackers were dipped.”
It seems like what Mom said was right: germs are everywhere.
A second experiment tested bitten vs. unbitten in water with ph levels typical of food dips. The more acidic solutions were tested after 2 hours and they found that the bacteria lowered from the initial reading immediately after the bite.
Next different “dips” were tested. Salsa, chocolate, and cheese dips (all different ph levels and thickness.) They tested bacteria in the dips after bitten crackers were dipped and after unbitten crackers were dipped. Additionally they tested hours later to see how the colonies of bacteria faired after time had gone by.
When single dipping there was no detectable amount of bacteria present.
Once double dipping took place there was bacteria and here is how it looked on the different dips:
Salsa had five times more bacteria (1000 bacteria/ml of dip) compared to chocolate and cheese dips (150-200 bacteria/ml of dip.)
Two hours later the salsa dropped to the same numbers of the chocolate and cheese dips. The acid in salsa helps to kill of bacteria over time.
The original results of more bacteria in salsa is thought to be related to the thickness. The salsa is not as thick as the chocolate and cheese counterparts. This means more dip (salsa) is touching the cracker and falling back in the bowl. As it falls back into the bowl it holds on for dear life to the bacteria that had reached out from the double dipper’s mouth. “Please pull us up too”, says the salsa as it careens back into the bow. “We can’t do it says,” the bacteria. And then the salsa says, “if we are going down you are coming down with us”. And they do in fact bring some with them. Thus polluting the salsa with the bacteria from double dipper.
How Worrisome Is This?
Well, it’s worrisome like shaking hands with a person that sneezed or coughed on their hand. Some calculated risks are taken when living in society and you are going to run into bacteria. By all means don’t skip the party in fear. In the same token if you see a person over at the salsa double dipping – don’t run towards them to get slopping seconds. You don’t know what dormant bacteria they might have.
Also, hey double dippers – when you live in polite society you also should maybe try to protect your fellow humans by not double dipping. If you must dip more put some on a plate and dip that way. After all I want you to have a good time. Just stay away from my salsa. You wouldn’t like me when I don’t have salsa.
For a great deal more information on this study and what it means please head over to the article titled Is Double Dipping A Food Safety Problem or Just a Nasty Habit?