I will be cutting up my deer today, and this is my first time doing it. Dealing with the scraps that I will grnd into burger. I have read that it is easier to grind, when the chunks are half frozen. So that being said, can I just put all the scraps in the freeze for a while, and grind it all up later? I am planning on mixing about 15% Beef Fat with it. Can I just go to the grocery store and buy that from the meat department? Thanks for all your help.