Forsøg med protein?

Du kan bruge Kjeldahl metoden til at måle indholdet af nitrogen som (næsten) er proportionelt med indholdet af protein i en fødevare. Du bliver dog nødt til at opløse din prøve i vand.

Tusind tak :) men er der ikke et alternativ simpel forsøg?

Her er noget. Har ikke selv prøvet men det lyder meget simpelt:

Protein station

Testing for the presence of proteins - Biuret test Show students the available foods for testing. Ask them which ones they expect to contain protein. Demonstrate to students how to perform the test. Put a food item containing protein into a test tubes (i.e. milk or tofu). If it is not a liquid, add some water and mash it well. Also set up a control, a test tube containing a liquid that does not contain protein (i.e. water). Add about 2ml of Biuret reagent to the test tube. Show students the positive - purple or pink - test result indicating the presence of protein. Discuss the importance of a control. Allow students to test various food items for the presence of proteins (see student handout). Ask students whether they are able to tell which food items contain more protein than others. Be careful: Biuret reagent can stain your skin and fingernails!! (They contain proteins!)