https://www.bzypetfood.com/products/freeze-dry-chicken-liver-cube.html Freeze Dried Chicken Livers for Dogs It's vacuum freeze-drying, where fresh meat is put in a -36C vacuum environment to freeze rapidly and sublimate into water until dry. The freeze-drying process preserves the nutrients in the ingredients and kills any microbes that might be present. Truly zero add, safe, delicious and healthy pet snack.