The mid-1800s were a time of great migration, when people from the East Coast crossed the Great Plains in search of a better life, and more specifically, California gold. Traveling in covered “prairie schooners” proved to be hazardous both physically and in keeping food from spoiling. Gail Borden Jr. (1801-1874), a New England businessman and inventor who transplanted to Texas, turned his attention to developing condensed, portable food that didn’t spoil.
His first attempt was a “meat biscuit,” dehydrated meat compounded with flour, that would not spoil. But it also was reported to be unpalatable. Though the U.S. Army endorsed it in 1850, Borden had to abandon efforts to market it when he ran out of money. Around the same time, he had begun experimenting with a process for condensing milk.
While milk is a staple and nutritious drink today, at the time it was risky to consume. Cow milk was ridden with bacteria, and if it wasn’t consumed within several hours in the summer, it spoiled in the heat, causing milk poison or milk sickness. Borden, who had been a farmer, leveraged his experience in drying foods to try to make milk safer.
“He knew milk to be the most perfect single article of food—the only one, in fact, which when fed alone, will sustain life, and yet the most perishable and the most difficult to get to the large cities in its original purity and freshness,” Ollie E. Reed, chief of the USDA’s Bureau of Dairying from 1928 to1953, wrote about Borden.
Reed wrote that Borden didn’t know about germ theory, but he had learned from the meat biscuit experience that preventing decomposition was a key. There had been many previous attempts to solidify milk or find a suitable substitute for it, but Borden wanted to make something better, according to Reed.
Borden’s first patent filing in 1853 was for an evaporation process done in a vacuum in an effort to protect the milk from air, much in the way a cow transfers milk to its nursing young. While that application was refused, he tried again in 1856 and succeeded. In the abstract to that patent, Borden wrote he had two inventions: a process for concentrating and preserving milk by coagulating and rearranging the albuminous particles in combination with the evaporation of the fluid in vacuo; and the preparatory coagulating and rearranging of the albuminous particles done as part of making concentrated or condensed milk.
In describing the rationale for the process, Borden wrote, “All organic substances are injuriously affected by the atmosphere, and are liable to reaction among their constituent elements; hence the deterioration of milk is greatly influenced and accelerated, though not wholly caused, by exposure to air.”
He continued, “This demonstrates that the less milk is suffered to be acted upon by the external air, the better its condition…and has led me to perform the concentration, which is one object of my invention, in such a manner as to exclude the milk as much as possible from contact with the atmosphere as it is being concentrated.”
The process involved a preliminary heating of the milk as soon as possible after milking the cows until its albuminous particles coagulated. This kept the vacuum heating vessel from being coated with extra albumin. Borden recommended in his patent abstract preheating in tin, brass, or copper cans placed in a bath of boiling water from 150 to 200 degrees Fahrenheit, depending on whether the end result is plain condensed milk or preserved milk. He then recommended straining the milk into a metal reservoir with a steam-jacket, into which the milk was brought to the boiling point and then drawn into the vacuum-boiler (to prevent air contamination) using atmospheric pressure through a pipe leading to the pan. The milk was then evaporated and concentrated by superheating it, checking its consistency regularly with a gauge, transferring it into tin cans that usually held 40 quarts, and then cooling it with ice to below 50 degrees Fahrenheit for plain concentrated milk and to 56 degrees Fahrenheit for concentrated milk that has been combined with sugar or other extracts. The result was Gail Borden Eagle Brand condensed milk. Eagle Brand’s website notes its brand was the top selling sweetened condensed milk for more than 147 years. In 1938, now-famous “spokescow” Elsie the Cow was introduced. The brand is now owned by the J.M. Smucker Co.