Test materials: electronic balance, water bath, 100 ml beaker (or digestive tube), glass rod, small spoon, dropper, dilute iodine solution, distilled water, starch, amylase.
1. Prepare the starch solution, weigh about 0.5 g of starch, and dissolve it in 30 ml of distilled water.
2. Add 1-2 drops of dilute iodine solution to the starch solution and shake it until the color develops (amylose is blue and amylopectin is reddish brown).
3. Put the above starch-iodine mixture in a 40°C water bath for about 3 minutes.
4. Add no more than 0.1 g of amylase and stir for about 1 minute to observe the fading reaction.
Test result judgment: The faster the fading time, the more thorough the fading, indicating that the higher the efficiency of amylase enzymatic hydrolysis of starch.
Add dilute iodine solution to 8 test tubes, 1-4 test tubes show blue, 5-8 test tubes show reddish brown
1, 5 blank control; 2, 6 glucoamylase; 3, 7 medium temperature amylase