Subject: Does age of potato effect the rate at which catalase decomposes H2O2?

I have recently done an experiment which tests the effect of surface area 
of potato tubers (i.e. catalase) on the decomposition of H2O2. 

The test ran over a few days I had to use different potatoes which gave me 
a very "interesting" set of results. What I found out was that the older 
the potato I used then the faster the reaction and more O2 was given off.

I've tried to research this and what I've found is that there are 
different types of catalase enzymes (H2 donors etc.). Also in a case of 
infection a potato will produce more of these enzymes in order to combat 
the infection. I've been trying to think whether the older the potato then 
the more catalse enzymes it has produced. Why? I would suggest that on 
removing the potato from its shoots it immediately produces these enzymes 
as a safeguard(?). Also the older it is the softer it is suggesting the 
cells have lost moisture. On losing water I think the enzyme conc. would 
thus increase decomposing the H2O2 faster than a new potato. These are the 
only plausable reasons I could come up with. PLEASE could you tell me if 
I'm right and if so would you be so kind as to ellaborate my hypothesis 
(my own research has proved less fruitful than I had hoped!). If there are 
any other reasons I would be most grateful if you would inform me of such.

Thanks

Re: Does age of potato effect the rate at which catalase decomposes H2O2?