While today we take for granted the ability to preserve food for long periods of time with chemical additives and preservatives, during the early 1900s food spoilage was common. The most popular methods at the time, salt and spices, were not only ineffective but in the case of the latter, actually accelerated spoilage.
However, thanks to the innovations in food chemistry pioneered by National Inventors Hall of Fame® (NIHF) Inductee Lloyd Augustus Hall, these solutions were replaced by more effective preservative methods that revolutionized food storage.
An Early Determination
Born on June 20, 1894 in Elgin, Illinois, from an early age, it was clear that Hall was an unusually determined student with a gifted mind. Before graduating near the top of his class, he was captain of his high school debate team and competed in football, track and baseball. For his accomplishments, he was offered four college scholarships and decided to attend Northwestern University, where he earned a bachelor’s degree in pharmaceutical chemistry in 1916.
Right out of college, Hall was hired by one company thanks to a strong phone interview. Unfortunately, when he showed up to work on his first day, he was turned away because of the color of his skin. Undeterred, he began working as a chemist for the Department of Health in Chicago, and later as chief chemist at the John Morrell Co., a business specializing in meat processing.
This experience would prove essential when in 1925, Hall was hired as chief chemist and director of research at Griffith Laboratories, a food processing company where he would go on to spend most of his career.
The Flash-Drying Technique
While working at Griffith Laboratories, Hall began exploring the science behind curing meats. Though combining table salt with potassium nitrate had been the popular curing method, he believed that he could improve the process and began experimenting with combinations of sodium nitrite, sodium nitrate (saltpeter) and sodium chloride (table salt).
However, when he began using this new method, Hall realized that the sodium nitrite and nitrate were affecting the meat much faster than the table salt, causing the meat to fall apart before preservation could occur. His solution would change the meat curing industry forever. First, he mixed the three different salt chemicals together. Next, he evaporated the mixture over hot metal rollers, creating flash-dried crystals. In its new form, the mixture was then able to properly preserve the meat.
Though a clear improvement over previous methods, Hall realized these new flash-dried crystals were absorbing moisture out of the air when stored, reducing their effectiveness. To fix this, he created a solution of glycerin and alkali metal tartrate which transformed the crystals into a powder, solving the problem.
An Enduring Legacy
Throughout his career, Hall earned over 100 U.S. and foreign patents in food chemistry. In addition to the process of flash-drying salt crystals that is still used to this day, he introduced the use of antioxidants to prevent spoilage of fats and oils in bakery products.