Science Buddies: "Ask an Expert"

I am doing a project on measuring how temperature affects the content of vitamin C in orange juice. I thought of seeing how temperature would affect orange juice. I am in honors chemistry and I need to make this porject more advance and at a high school level. Any help would be appreciated. THANK YOU VERY MUCH

Hi,

You have made a good start on your project by thinking of a topic you are interested in.

The science buddies website has information for doing a vitamin C project:

https://www.sciencebuddies.org/science- ... p043.shtml

You will need to set up an assay for vitamin C and do a controlled experiment with temperature as the independent variable and vitamin C content as the dependent variable.

However, since you mentioned that you are in an honors chemistry class, and you realize that you need a more advanced project, I recommend that you do more background reading on your topic and try to ask a question about vitamin C that has not been answered before. This would give you a truly original project for this assignment.

Here are a couple of references to get you started?

http://www.nutritionj.com/content/2/1/7

http://fnic.nal.usda.gov/nal_display/in ... 4_id=10591

http://lpi.oregonstate.edu/infocenter/v ... crefs.html

Be careful when doing your background research; you should use scientific journals for your sources of ideas. There are a lot of non-scientific sources on Vitamin C on the internet.

You should keep in mind that you will want to do a carefully controlled experiment based on literature references and with a purpose, based on scientific facts. For example, you might want to study the protective effects of selenium on vitamin C in grapefruit juice.

Let us know if you have any questions.

Donna Hardy

Thank you very much for providing me with links to help me get started on my background research. I recently cam up with the idea to test if the content of vitamin C will change or remain the same in the presence of stomach acid. Should I use a potassium iodate or should I use a iodine iodate? Thanks!

Hi,

Did you read something in a literature reference that gave you the idea for testing the effect of stomach acid on ascorbic acid? What would be the purpose of this project?

I'll explain the reason for my questions. Here is a reference that documents the effect of different types of sample vials on the concentration of vitamin C. This was a vitamin testing laboratory and the authors had noticed that results were not consistent. They found that the sampling vials contained metal ions and they determined the best way to clean vials to eliminate the problem.

http://www.clinchem.org/cgi/content/full/47/8/1463

The authors of this paper had a purpose for their project, the study involved doing lots of vitamin C analysis, and their carefully controlled experiments helped them solve the problem with the assay.

I would encourage you to keep reading more literature to develop your purpose.

You use iodine for vitamin C analysis. I'll explain the chemistry of the analysis before you start your experiments.

Donna Hardy