How should I measure nutritional value in food? PLEASE HELP

[sciencefair258]

Hi, my science fair topic is to find if microwaving food decreases nutritional value in food, but I am looking for methods to test.

I am thinking to microwave/boil vegetables (with the original vegetable as a control) and compare the nutritional value, but what are some methods for testing?
How can i test for things like iron, fibre, carbohydrates, vitamins and etc. in food?

Thanks

[VSegarra]

Hello!
Your project sounds very interesting! One of the ways you can measure nutritional value in liquids (for example fruit and vegetable juices) is using a refractometer or Brix meter. Nutrients (sugars, vitamins, etc) in a liquid can cause light to bend or refract. A refractometer can measure the refraction index of a liquid, giving you some indication of its nutrient content. Hope this helps!!
Veronica

[sciencefair258]

Acutally, I have decided what I want to measure:
I would like to measure the amount of vitamin c in potatoes using titration, but I'm confused about the titration method!!

[VSegarra]

Hello!
For help understanding titration you can go to your textbook or teacher. You can also find online resources. Best wishes for your research!
Veronica