Every year, one out of every six Americans suffers some form of food poisoning, according to statistics from the Centers for Disease Control and Prevention (CDC). Of those 48 million people, 128,000 are hospitalized and 3,000 die from illnesses transmitted through contaminated food. About 80 percent of foodborne illnesses are caused by unknown agents but of the known pathogens causing food poisoning, the bacterial agent Salmonella caused the highest number of hospitalizations and deaths among all such pathogens. Annually, there are are about 1 million cases of Salmonella affecting Americans, including about 19,000 hospitalizations and 380 deaths every year.
The first strain of Salmonella was isolated and discovered in 1885 by American veterinary scientist Dr. Daniel E. Salmon, who mistook the bacteria as a potential cause of hog cholera. In 1888, a major outbreak of food poisoning occurred in Frankenhausen, Germany, caused by an organism from the same genus of bacteria. The Bacillus genus, which included these serotypes was renamed to Salmonella in honor of Dr. Salmon’s work in the field.
The 2016 inductee class for the National Inventors Hall of Fame includes two microbiologists whose contributions to the field of food safety have helped to keep many foodborne pathogens, especially Salmonella, in check: John H. Silliker and Welton I. Taylor. These two scientists worked together to develop more effective monitoring techniques for food products in response to the growing concerns in the mid-20th century regarding Salmonella outbreaks, especially those which hit children the hardest. With the anniversaries for important patents issued to both of these food safety engineers having passed in early March, we thought we’d visit their scientific contributions from in our Evolution of Technology series here on IPWatchdog.
In the late 1950s, an outbreak of Salmonella was traced back to dried egg yolk used in baby food produced by American food processing business Swift & Company, based in Chicago, where both Silliker and Taylor were employed. Silliker and Welton soon discovered that the process used to analyze egg yolks for the foodborne pathogen had been taken from clinical laboratory methods that didn’t transfer well to food production environments.
Both Taylor and Silliker are listed as inventors on U.S. Patent No. 2876108, entitled Processing of Food Materials, issued on March 3rd, 1959. It claimed a method of controlling bacterial growth in a food material which comprises adding to the food material containing an objectionable bacterium in a bacteriophage having predetermined properties of destroying said bacterium and maintaining said phage in contact with said bacterium under suitable conditions whereby said bacterium are substantially reduced. This process, which could be adapted to destroy bacterium in ham, sausage and eggs, involved the introduction of a bacterium into such food material which inhibits the growth of bacteria such as Salmonella as the food dries or cures. Along with this patent, Silliker and Taylor co-authored a series of five papers on salmonellosis and the role of Salmonella in food safety.
Silliker would end up leaving Swift & Company shortly after this breakthrough and he spent much of the following decade at St. James Hospital in Chicago Heights, IL, where he was able to use the hospital’s laboratory facilities to continue his research into Salmonella and related foodborne illnesses. Increased efforts at the U.S. Food and Drug Administration (FDA) to combat Salmonella outbreaks in the mid-1960s shifted Silliker’s focus and in 1967 he founded Silliker Labs, a company dedicated to developing technologies for better food safety and quality. Silliker’s contributions to the scientific field of food safety has earned him awards and recognition from the International Association for Food Protection, the American Academy of Microbiology, the Institute of Food Technologists and NSF International.
Soon after the breakthrough discovery for reducing the risk of Salmonella poisoning from processed foods, Taylor also left Swift & Company and entered the world of medical science by taking a position at Chicago’s Children’s Memorial Hospital in 1959. His work in foodborne illnesses attracted the attention of the World Health Organization and in 1961, Taylor spent one year split between facilities in London and Paris bringing his knowledge of microbiology and food safety to British and French scientists.
Upon his return to the United States, Taylor shifted his focus slightly to tackle the problems posed by Shigella, a bacteria similar to Salmonella which can contaminate food and cause food poisoning. His work led him to develop devices capable of detecting foodborne pathogens and March 1st marks the anniversary date of the issue of U.S. Patent No. 4010078, entitled Device for Use in the Identification of Microorganisms and issued to Taylor on March 1st, 1977. It claimed a device having a microorganism culture medium receiving portion having a plurality of culture medium receiving compartments, a cover with a top wall, an upwardly extending side wall which engages and maintains the top wall of the cover; the side wall also includes an inwardly extending section along a horizontal plane of the culture medium to provide an orienting recess for a covered air passageway which enables an atmosphere which favors the growth of microorganisms to be selectively established over the culture medium in the compartments of the receiving portion while the cover shields the culture medium from contaminants. This device served a need for accurate yet rapid identification of microorganisms having clinical significance, especially pathogenic non-fermentative Gram negative rods and yeast pathogens, and has the further advantages of being lightweight, compact in size and readily allows observance of microorganism generated activity in the culture media.
Taylor’s microorganism detection devices were approved by the FDA, as well as similar food safety regulatory agencies in Canada and Europe, for their use in food processing industries to certify food as bacteria-free. Taylor even opened a company to try and commercialize his products, Micro-Palettes Inc., but this venture folded in 1988. His work in the detection of foodborne pathogens led the CDC to name a bacterium, Enterobacter taylorae, in honor of research produced by him as well as a British colleague, Joan Taylor; Welton Taylor was the first African-American scientist to be honored in this way. He was also the first African-American to serve on the editorial board for three different scientific journal publications.
Foodborne illnesses caused by the ingestion of Salmonella continue to occur and the FDA offered up to $400,000 for innovative solutions in food safety in a week-long competition occurring last July. In 2014, researchers from Purdue University took home an FDA prize for food safety tech with a microfiltration method which provides accurate testing for Salmonella within a couple of hours, an improvement over the multiple days required for other tests. The private sector is also involved with the development of test arrays for Salmonella detection and in December, the analytical method standards organization AOAC Research Institute approved an extension for Salmonella test arrays incorporating new technology developed by DuPont (NYSE:DD).