Evaporated milk comes in canned form, and is evaporated due to the process of removing water from the milk. When you open a can of evaporated milk, you’ll notice the milk is much thicker than ordinary milk you’d buy at a grocery store. This method of storing milk became popular because the cans of milk could keep far longer than fresh milk, and didn’t require refrigeration until after they were opened. About 60% of the water is removed from evaporated milk, accounting for its thickness.

Evaporated milk is made by exposing fresh milk to high heat so water essentially evaporates. The end result is a dense, high calorie milk that is usually fortified with vitamins A & D, just like fresh milk. Yet because of the evaporation process, the concentrated milk you get when you buy a can of evaporated milk has a higher concentration of vitamin content. You can water down the milk if you intend to serve it as regular milk, by adding equal amounts of water to the evaporated milk. This will lower calorie content and vitamin distribution. You may also find low fat versions of evaporated milk on the market.

Dairy farmers developed evaporated milk over 100 years ago. The company Borden was first on the market with condensed milk, to which sugar was added to produce a very sweet product. The main difference between evaporated and condensed milk in the US is that no sugar is added to the evaporated form. It is merely whole milk from which water has been removed. This is not the case in other countries, where you’ll find many brands of evaporated milk that contain sugar.

Sugar acts as an excellent preservative, extending the life of condensed milk, but it’s important to note this distinction between condensed and evaporated milk, especially when you are baking. While some recipes call specifically for condensed milk, like quick fudge recipes, other recipes, like many for pumpkin pie require evaporated milk. You can’t substitute one of the other unless you want to add or take away from the total sugar in your end product. Most pumpkin pie recipes, for instance, are made too sweet by adding condensed instead of evaporated milk; while fudge recipes may not be sweet enough if they’re made with evaporated milk.

Some people like to use evaporated milk for sauces. Gracie Allen, the wife of George Burns, boasted of her mustard sauce made from evaporated milk. It can be a good substitute for cream, slightly lowering overall calorie content, and some people enjoy adding it to coffee or tea. Some argue that milk from cans has a metallic taste. Still, if you need milk around but lack refrigeration, as in the case of emergencies where you might lose power, evaporated milk is an excellent choice. Do note that if you lack refrigeration, you cannot keep evaporated milk out without spoiling it.

Once the can is opened, you should follow the same basic rules for the shelf life of fresh milk. If you do reconstitute the milk to serve at a meal, in an emergency, or while camping, any milk left over should be thrown out since it will spoil easily. If you have access to a fridge, merely cover the leftover milk, where it will store in the fridge for about three to four days without spoiling.