Science Buddies: "Ask an Expert"

We are conducting the experiment to determine which skin moisturizer is best for dry skin.
We are using jell-o to represent skin.
During the 2 week period, should the jello be kept in the refrigerator?

Hi!

That looks like a great project. And it's a great question you raise. I haven't done this experiment, but I would leave them out at RT if you can control that reasonably well - because you are looking for moisture loss to the air, which will be greater out in the room, not in the fridge. BUT if the products are getting too soft or the geletin isn't keeping firm (what temperature does jello melt at??), you may look for a cooler spot - like a basement, or or the fridge if you need to. The lids should be kept off, dishes in a single layer, away from drafts, fans, heat source, etc, that will speed drying.

I hope that helps. Let me know if you feel the experiment is going bad due to your location... but I don't expect that to happen!

Thanks,
Tonya

I haven't done that project either and in all the references on the web to this procedure (including ours), no one says whether it should be refigerated or not. I disagree with the idea that you'll get more evaporation at room temperature. The refrigerator is an incredibly drying place You can see that pretty clearly if you leave butter or cheese uncovered - it turns into a dense yellow, dried out blob pretty quickly. I would also suggest that room temperature is better if it's not so warm that the gelatin melts.

The content group has a meeting this afternoon and I'll ask to get you a definitive answer.

Howard

The response from the project developer: "I left them out at room temperature, in a relatively cool room (a basement room, but I'm not sure how much this matters). I amazingly didn't see any mold or anything, but this is probably because the lids help protect them from various microbes flying around."

I had asked about mold, and we're hypothesizing that since the cooling down from boiled to gel was done with the lids on and then the gel was quickly covered with moisturizer, that there was minimal exposure to microbes in the air.

I hope that helps.

Howard