Food Safety Lab
The bacterial storage freezers, called the freezer farm by lab members, hold over 60,000 samples of bacteria. These freezers are kept at negative 80 degrees Celsius, or negative 112 degrees Fahrenheit. Each freezer tower holds 12 boxes, with each box containing 96 different bacteria. Many of the samples came from humans who were sick from foodborne illnesses. Because the lab’s stored bacteria developed outside of a lab and are from living samples originally, companies often contact the FSL, asking to use their collection. Most bacterial samples have been DNA fingerprinted, and the information is stored in the FoodMicrobeTracker database, kept by the lab.
Researchers use the tissue culture facility for growing human and animal cells in the lab to better understand how bacteria infect these cells and how infection can be prevented or treated. Human and animals cells grown in the lab also help determine whether specific bacteria and bacterial isolates have the ability to cause human disease.
The lab uses their Pulsed-field Gel Electrophoresis (PFGE) equipment to DNA fingerprint bacterial isolates. Each device works by applying an electric field that periodically changes direction to the DNA: one through the central axis and two at an angle of 60 degrees on either side. PFGE is a gold standard method for fingerprinting pathogenic organisms, and the lab utilizes these machines regularly when finding the source of foodborne illness outbreaks.
The PCR machine area is a workspace in the FSL lab that allows researchers to amplify single copies of a piece of DNA, generating many copies of a particular DNA sequence. Lab members routinely use the PCR machine to identify bacteria from food samples as well as perform DNA-based subtyping.
The FSL employs anaerobic chambers to grow microorganisms that do not grow in the presence of oxygen. The chambers maintain an anaerobic environment and appropriate humidity, allowing the researchers to culture pathogenic and spoilage bacteria. Lab members use the anaerobic chambers to grow Clostridium, a bacteria that causes botulism and colitis. By growing the bacteria, researchers are able to study the pathogen.
The lab utilizes this space to prepare the media and reagents needed to isolate, grow, and characterize bacteria. The plate-pourer allows the FSL to prepare large numbers of agar plates that contain bacterial media so that the lab can conduct large-scale studies to collect and test large sets of samples.
The spiral plater helps lab members rapidly count the number of bacteria in a sample. A sample is dispensed onto a petri dish rotated by the spiral plater at a constant speed. The plater has the ability to vary the sample volume delivered as well as concentrations of the sample, depending on the needs of the researcher. This method provides each dish with an equivalent amount of sample, distributed equally. Spiral plating is an approved method by the United States Food and Drug Administration and is used extensively for microbiological testing of food products by researchers nationwide.
The Food Safety Lab (FSL) at Cornell University translates research into real global improvement. The FSL studies bacteria that cause foodborne illness. The lab is equipped to handle bacteria under biosafety level-2 conditions, which requires extra precautions to protect researchers and the environment from potentially hazardous bacteria such as Escherichia coli (E. coli) or Salmonella.
The FSL has developed algorithms to help the commercial produce sector predict where bacteria that cause foodborne sickness be found. The research is especially helpful to farmers who grow sensitive products that are consumed raw. Researchers have also helped processing plants by DNA fingerprinting microbes from processing facilities to learn how bacteria move in facilities and where they hide. Results from DNA fingerprinting allow the FSL to set up strategies for reducing contamination in processing plants. The FSL also works with the New York State Health Department and the Center for Disease Control to develop and implement tools for DNA fingerprinting. The lab’s collaborations have made it possible for New York State to be better positioned to detect sources of foodborne disease outbreaks more efficiently.
Cornell faculty, PhD students, postdoctorates, technicians, and undergraduate researchers from the College of Agriculture and Life Sciences come together in the FSL to create a collaborative environment. Researchers who are not directly involved in pathogenic microbiology, such as engineers and material scientists, have used the lab while designing metal surfaces that resist bacteria or biosensors that detect foodborne illness. Students who work in the lab have successful careers in food safety because they become well trained on the practical side.
“The Food Safety lab provides a unique environment for people from a lot of different backgrounds to come together and help solve pressing issues regarding food safety, which affects everyone in the world,” says Martin Wiedmann, Gellert Family Professor in Food Safety. “We bring new technology and new tools into solving an old problem.”