Because it could be reconstituted by adding water, evaporated milk was popular before refrigeration as a substitute for perishable fresh milk. In present times, household use is most often for desserts and baking. When mixed with an equal amount of water, it can be substituted for fresh milk in recipes.
Evaporated milk has a shelf life of months (and sometimes years), depending on the brand.
According to the U.S. Government (21CFR131.130): "Evaporated milk is the liquid food obtained by partial removal of water only from milk. It contains not less than 6.5 percent by weight of milkfat, not less than 16.5 percent by weight of milk solids not fat, and not less than 23 percent by weight of total milk solids ... It is homogenized. It is sealed in a container ... processed by heat ... to prevent spoilage."
Vitamin D: Each fluid ounce of the food shall contain 25 International Units (IU)
Vitamin A: is optional, but if added, each fluid ounce of the food shall contain not less than 125 IU.
Condensed milk was introduced to the U.S. by Gail Borden which he made using a process under the patent issued on August 19 1856. It became popular for those people who were remote from farm sources, since it was capable of long term storage. The invention of evaporated milk followed three decades later when John B. Meyenberg emigrated to the U.S. from Switzerland where he had devised the process, but had no support to begin production. He obtained two U.S. patents for his process and sterilizing apparatus, issued on November 25 1884. He formed the Helvetia Milk Condensing Company on February 14 1885, with a number of farmers and businessmen of Highland, Illinois, as stockholders. By June 14 1885, the first canned "Highland Evaporated Cream" was ready to be marketed.
There were problems with the new product, with premature spoilage in early batches. Over the next few years, Louis Latzer and Dr. Werner Schmidt solved the problems due to bacteria. With the marketing efforts of John Wilde, the company became successful as Pet, Inc., and is now part of General Mills.
John P. Meyenberg, son of John B. Meyenberg, was the first American to evaporate goat’s milk. He started the Meyenberg business in 1934, supplying goat milk products that are more digestible than cow's milk, and an alternative for people (like himself) who were allergic to cow’s milk.
Evaporated milk is fresh, homogenized milk from which 60 percent of the water has been removed. It is then chilled, fortified with vitamins and stabilizers, packaged, and sterilized. A slightly caramelized flavor results from the high heat process, and it is slightly darker in color than fresh milk. The evaporation process also concentrates the nutrients and the food energy. Thus, for the same weight, undiluted evaporated milk contains more food energy than fresh milk.
In Malaysia, evaporated milk contains palm oil. It is one of the ingredients to make Teh Tarik in Malaysia and Singapore. Also it is added in brewed tea and coffee to make Teh See and Kopi C respectively.