How germy are baby carrots?

It turns out that the convenient, easy-to-eat baby carrots are covered with bacteria. They often feel slimy and now we know why. It is far better to buy and peel your own big carrots. In fact, any pre-cut produce is risky. Packaged pre-sliced apples are also loaded with bacteria. 


 For these experiments, I compared ready-to-eat carrots and whole carrots.

First, I rolled 3 baby carrots (directly out of a new bag) around on an agar plate using a sterile swab. 

Then I peeled a large carrot under running warm water. 

I cut the carrot into 3 sections and rolled them around on another agar plate using a sterile swab.

I incubated the plates in my warm incubator overnight and examined the plates in the morning. I have repeated this experiment several times with 4 different brands of carrots (some organic and some not organic). The ready-to-at carrots all contain much more bacteria than a big carrot peeled under running water. I am buying the big carrots from now on. My children actually prefer eating a big, long carrot because they like to pretend to be "Bugs Bunny". 

I have repeated this experiment with several bags of baby carrots and they are all very germy. After doing these experiments, I always buy and peel long carrots. 

Negative Control

I wanted to make absolutely certain that my tap water and clean gloves were not contributing bacteria to my experiments. So, I put on a clean pair of gloves, got them wet under the tap water, and rubbed them on a clean agar plate. I do this control for all of my fruit and vegetable washing experiments. 

I incubated the plate overnight and was pleased that there was no bacterial growth at all the next day.