I feed my kids fresh broccoli every day at lunch. I rinse it off with warm tap water and that seems to do reasonably well at removing germs. Fresh Broccoli For this experiment, I wanted to determine if simply rinsing in tap water did a good job cleaning broccoli. First, I rubbed an unwashed piece of broccoli on one half of an agar plate.
Then I rinsed another piece of broccoli under WARM tap water for 20 seconds. I rubbed it while I was rinsing it.
I rubbed the rinsed broccoli onto the other half of an agar plate. The plates were incubated overnight.
The results show that just rinsing in WARM water and rubbing does a good job cleaning broccoli. I have repeated this experiment a few times and warm water is more effective than cold water.
Negative ControlI 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.
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