Test extraction and Test for Vitamin C

Today we got some foreign oranges to the laboratory in order to extract juice from them. We used the traditional orange juicer in order to make the juice. However, we noticed that the pulp in the juice was obstructing our 25mL pipettes and not allowing us to measure 25mL of juice.

Hence we needed to revise our methodology. We decided to get a cheesecloth next time to filter the juice. We also decided to use an electronic fruit juicer next time instead of the traditional juicer since this produces a smoother juice.

Despite not being able to calculate 25mL of juice, we still attempted to titrate some juice against iodine to see whether the titration works. We added some starch indicator and titrated the juice.

The titration worked. At end point the colour of the juice darkened.

In the next meeting we will be better prepared and we will be able to make the first actual titration on orange juice. The titration of today served as a test.