Are enzymes killed off in preserved food?

[harryf]

I was reading on how enzymes can remove vitamins and other nutrients in vegetables and fruits. I was wondering if preserved food contains any significant level of enzymes or have they been destroyed during the manufacturing process?

 

[Michael in FtW]

When vegetables are frozen they are blanched to stop/greatly retard the enzymatic actions before they are frozen. I believe this is also true for some/most fruits ...

Canned foods are also safe, regarding the loss of nutrients due to enzymes, since they are either pre-cooked before canning or are actually cooked in the can during canning - but the processing leaches vitamins and nutrients into the liquid they are packed in ... so unless you incorporate the can liquor into the dish in some way - you're probably throwing away more nutrients than the enzymes consumed.

 

[girdhar]

Hi,
there are various factors affecting the nature and existence of the enzyme. Basically all the enzyme are made up of protein.the vitamin are also the heat sensitive organic compound .
so the nature of the enzyme plays an important role whether it will act adversely or not .

 

[harryf]

I was reading on slow cooking and it says that enzymes would kill off the vitamins. But if I were to blanch it first, then the enzymes would be killed off; therefore, leaving the vitamins intact.

How true is the above? I would like to keep as much vitamins as possible.