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Hello

I am doing the experiment on hidden sugar metabolism ( hidden sugars in my food) (https://www.sciencebuddies.org/science- ... metabolism)

I need some help and direction on some results I am getting.
When I am testing with different foods ( I used milk, ketchup, mayo ). I made the 1:10 dilution and tested with the glucose strip. After 10 min when I tested with the glucose strip, every solution except milk showed 1%. Milk remained at 0% ( no change in color from blue). But when I tested after 20,30,40,50 minutes.. the results remain the same ( 1% - glucose strip i.e was the same green color).. does it mean there is no more glucose conversion ? What does this mean ? How do I interpret this results ?

Appreciate if someone can help and guide me where I am doing wrong... thank you so much in advance

Sincerely

Hi - We want to make sure that you have carefully followed the procedure, so please do go back and look at the steps to make sure you are testing the right thing.

Did you verify that the glucose strips work with the glucose dilution series?

Note that in this project, you don't do a time series with the foods, but with the sucrose solution to test the invertase activity. The food is only tested at the linear time point determined from the sucrose test before. Make sure that you followed the procedure as described regarding testing the invertase activity with the sucrose solution to determine the linear time point?

After adding the invertase to the food, you only measure one time -- at the linear time point. Did you add the enzyme? If not, the glucose concentration won't change.

I hope this information helps you troubleshoot the steps you have done.

Amy
Science Buddies