Temperature and beef liver enzyme

I did an experiment on the effects of changes in temperature on the reaction of catalase in beef liver. I put a small piece of beef liver in hydrogen peroxide (with different temperature) for a minute and used a gas syringe to measure the amount of oxygen produced. My result is that as the temperature increased, the amount of gas produced kept increasing as well. However, I know that there is supposedly an optimum level, and the reaction should decrease after that level. I am not sure what I did wrong and what temperature should have been the optimum level.

(I would do my experiment again, but our teacher said we cannot do any more experiments.)

I would really appreciate it if anyone can advise me, send me a link to where the data is already provided, or help me do the experiment for me (I will send detailed steps).