Science Buddies: "Ask an Expert"

We have completed our project and our hypothesis was wrong. However, we are confused about other results. This is what we did: We took eight hot dogs (beef/chicken/pork) weighed and measured the circumference before mummification. We then rolled each hot dog in a separate mixture of salts and even used one hot dog with no salts. Our mixtures were as follows:
Dog 1: No salts
Dog 2: Epsom/table/baking soda
Dog 3: Epsom/table
Dog 4: Epsom/baking soda
Dog 5: Baking soda/table
Dog 6: Baking soda only
Dog 7: Table salt only
Dog 8: Epsom salt only

The dog that lost the most in weight and circumference was supposed to be the best mummified.

We then wrapped the dogs in gauze and put each in an individual lunch baggy, placed the baggies in a plastic container and in nine days observed our results.

Our theory was that the ancient Egyptians, who used a main ingredient of baking soda, did NOT have the best mummification technique. We predicted that the dog with all 3 salts would be the best (theory that each salt took out water and we would multiply this value by 3 if we use all together) This was my son's prediction (he is in 11) I predicted it would be Epsom salt (I thought of healing powers)

Our observations seem wacky to me. First, the hot dogs stunk to high heaven!!!!! We remeasured and reweighed. The dog that lost the most was the Epsom salt dog. However, the baking soda dog (ancient Egyptians) actually looked more like the original dog before mummification. It also gained weight, and how can that be possible? The dog with no salts also lost weight and circumference, but we also observed that it looked like rotting flesh. We contributed the weight loss and circumference loss to the fact that as we unwrapped it, some of the dog stuck to the gauze and it was just rotting!

So....... how do we put this in our report and how do we know that we didn't mess bleep up? Is it possible that the baking soda dog could gain weight or did we do bleep wrong? I thought the best mummified dog would be the one that weights and measures the greatest loss.

P.S. We noticed as we unwrapped the dogs that the ones with Epsom salt in them were extremely wet. The gauze was soaked and we contributed this to the mummification process. Thus the Epsom salt dog would be the best. Do we have the right idea?

Was there some reason that the mummification process was carried out in plastic baggies and a plastic container? A sealed environment will not allow evaporation and drying of tissues, hence the soft flesh like appearance at the end of the experiment. What you describe is typical of anaerobic decomposition.
I would suggest a repeat of the experiment but do not put the various treated hot dogs in baggies or a plastic container.

Matthew W. Mulanax

I believe we got the idea from another experiment. I equated the baggy with a tomb--which would not allow any air at all to get in. Our conclusion is due Monday. I am not sure if my son's teacher would let us conduct the experiment again. What would you suggest?

I am not sure how Egyptian mummies were processed before placing them in the tomb. It could be they were allowed to dry down before final placement.
I would explain the possible reasons for the condition of the hot dogs in your experiment – unfavorable packaging, no air exchange and an anaerobic environment favoring bacterial decomposition.
I would then ask for an opportunity to repeat the experiment using the conditions described earlier.

Good luck,
Matthew W. Mulanax

Hi Sammywells... It sounds like an interesting experiment (minus the smell!). I noticed in the Science Buddies project on mummification, air-tight plastic containers were also used:

Minding your Mummies: The Science of Mummification
https://www.sciencebuddies.org/science- ... p022.shtml

Amy
Science Buddies