Freezing potato mash made with root and fresh vegetables

To prevent the vegetable from going 'off' in the freezer.

From answers.com:

Blanching is the scalding of vegetables in boiling water or steam. Blanching slows or stops the action of enzymes. Up until harvest time, enzymes cause vegetables to grow and mature. If vegetables are not blanched, or blanching is not long enough, the enzymes continue to be active during frozen storage causing off-colours, off-flavours and toughening. Blanching time is crucial and varies with the vegetable and size of the pieces to be frozen. Under-blanching speeds up the activity of enzymes and is worse than no blanching. Over-blanching causes loss of flavour, colour, vitamins and minerals.

Broadly this is OK.

By broadly, I mean a couple of things. First, I'm assuming you are cooking the meat very thoroughly. That both means for long enough time to be completely thorough and hitting high enough temperatures to kill the main nasties off. Second, it naturally assumes you observe good practice with regard to not letting it sit for long periods, not co-mingling uncooked and cooked meet, yada-yada-yada.

I do what you're describing lots of the time myself incidentally, and have done for years without incident.

Of course, as I'm sure you know, one thing that is certainly a really bad idea is to freeze defrosted meat without cooking it.