Alternatives to evaporated milk include an equal measure of whole milk, half and half or light whipping cream. One of the substitutions that most closely mimics evaporated milk's flavor is whole milk simmered in a saucepan until it is reduced by approximately 60 percent. Dairy-free alternatives include thinned coconut milk, or a nondairy milk such as rice milk, simmered until it is reduced by 60 percent.
Powdered milk, or powdered dairy-free soy or rice milk, can also be used as a substitute for evaporated milk. Combine 2/3 cup of nonfat dry milk with 3/4 cup water to make 1 cup of an evaporated milk alternative. For a dairy-free version, combine 1 cup of rice- or soy-milk powder with 1 cup of boiling water to make 2 cups of evaporated-milk substitute. Place the powder and boiling water in a blender. Blend it until it is smooth.
Commercial producers make evaporated milk from whole milk or skimmed milk. After it is cooked down, evaporated milk is placed in airtight cans that are heated to kill any lingering bacteria, which is why canned evaporated milk typically has a long shelf life. It is often used in baking. It can also be used as an alternative to traditional milk and cream for use in beverages, sauces and other recipes.