Science Buddies: "Ask an Expert"

I know that this topic and project has been done but I want to make sure that before my son starts we have our bases covered.

Which cheese molds faster....we're using provolone, swiss, and american...I can throw in cottage if it would aid in proving his point. He is claiming that the swiss will mold quicker, and I have no idea why. (He's 9, it could be because it has holes-who knows ) In reading previous entries I know he needs to place them in a controlled area which we have covered, QUESTION should he place samples in the fridge as well????? I was thinking yes, because he could elaborate and say "Swiss cheese molds faster in open air than in the refridge" I won't lie, when I did science fair projects I faked my way through it but I want my son to actually experience it so if I'm not leading him in the right direction, please let me know. Thanks a bunch.

Oh, should he use actually three samples, one in the fridge, one in the dark, and one in the light and expand on the project farther? I think I like that....hmmmmmmm

Thanks, Cherifsmom

Hi,

This is a great science project. I’m happy to hear that your son has already formulated his hypothesis as this demonstrates that he is thinking about what will happen. However, since this is a science project, there are some other things to consider, so here are some suggestions for making this a really good project: Measuring the time that is takes different types of cheese to mold is a good experiment. The type of cheese is the independent variable and the time of appearance of the mold is the dependent variable. All other parameters in the experiment should be kept controlled, including the air, temperature and the light. The only thing that can vary is the type of cheese. The appearance of the mold should be meticulously documented, with observations made once or twice a day. Results should be recorded as they happen in a lab notebook. Surprisingly, doing three samples of the cheese in different conditions is not a better experiment because the number of variables is too high. It would be better to do three samples of each type of cheese, or do two samples of each type of cheese and repeat the experiment twice. Adding in different types of cheese, such as the cottage cheese would be a good addition to this experiment, but using just two cheeses is OK too.

Now, for the hypothesis. It seems that your son has just guessed at what will happen, and this is not the best way to do a science project. If he can give you a reason for his hypothesis that seems reasonable, then that’s OK. But if he can’t give you a reason that is based on science, then he needs to do more background reading.

First, he needs to know what a mold is. The Wikipedia article on mold contains some general information about the biology of molds. Perhaps you can help your son understand what a mold or fungus is and explain a little about the biology of this group of organisms:

http://en.wikipedia.org/wiki/Mold

Here's a website that describes the requirements for mold growth. This website is for buildings, but the information would also apply to cheese mold. You can review the requirements, (presence of mold spores, suitable food, appropriate temperature, sufficient humidity, air that is not moving) with your son to determine the optimum conditions for the experiment. Does your son know what the optimum temperature for mold growth is? Since the project deadline is coming soon, it will be important to know this so he will get results as quickly as possible.

http://www.fsec.ucf.edu/en/consumer/bui ... growth.htm

Here is some information from the Centers for Disease Control that includes some additional information on the significance of mold:

http://www.cdc.gov/mold/faqs.htm

Since the only difference in the results on this project will be the composition of the cheese, you son needs to try to find out what the moisture content of the cheeses are, and he needs to read the labels to find out if preservatives have been used, which will inhibit the mold growth. The holes in Swiss cheese would make a difference in the amount of air available. Molds do require oxygen for growth, and the holes in the Swiss cheese would provide more air and more surface area, which would be an advantage. Is there anything else about the difference in composition between the two cheeses that would make a difference in the growth rate of mold? Perhaps you could help with a Google search to find information that would show a difference in the cheeses and a scientific reason for saying that the Swiss cheese will mold first.

Please refer to the Science Buddies Science Fair Project guide for the details in doing a science project.

https://www.sciencebuddies.org/science- ... l?From=Tab

Good luck. Please let me know if you have any questions.


Donna Hardy

In addition to what Donna said, It depends on how complex you want the experiment to be. You already have your independent variable (the different cheeses), and normally it is recommended that you only have 1 type of independent variable, but as long as you use the different environments for each slice of cheese you should be okay. Make sure you don't only put provolone in the sun and swiss in the dark. All of the cheeses need to be in all of the environments. I hope this helps!

Thank you both very much. We are doing fairly well on this project. The teacher wants a minimum of 5 trials, so we adjusted our cheese. My son is checking and recrding his information as well as thinking of how he may have to present the project.

Of course as the mom, I have to figure out how to get him to explain it all to me so I can type up the report for him. I am not the mom who is going to do the project for him. I am here to help him, and aid in "collecting" his thoughts. Honestly, I am so green in the ways of science projects it's just not even funny.

Again, thank you both so much for your insight into cheesy science!