New extension poultry specialist to help producers navigate food safety risks, regulations

By Sarah Cato
U of A System Division of Agriculture

FAYETTEVILLE, Ark. – After a successful career in the poultry industry, Bill Potter has joined the University of Arkansas System Division of Agriculture hoping to give back to the industry and the university that means so much to him.

GIVING BACK – Bill Potter is excited to join the Division of Agriculture as faculty and give back to the industry and university that means so much to him. (Division of Agriculture photo.)

Potter joined the Division of Agriculture Sept. 3 as associate professor and Poultry Federation chair of food safety and processing extension, based in Fayetteville. Potter, who received his Master of Science and Ph.D. in poultry science from the University of Arkansas and has worked extensively with extension specialists through his career, said he was excited to join the Division of Agriculture as faculty.

“The poultry industry has provided me so many great opportunities, and I wanted to take this next phase of my career as a chance to return the favor,” Potter said.

“We are very excited to have Dr. Potter join the faculty in Poultry Science,” said David Caldwell, director for the Center of Excellence for Poultry Science for the Division of Agriculture. "He brings three decades of very relevant industry experience to our program, and that increases our reach and relevance with our commercial stakeholders. We are already seeing the benefits of his programming and outreach with industry partners.”

During his career, Potter has worked in poultry food safety, quality assurance and research and development for several industry leaders, including Conagra, Advance Foods, George’s Inc. and Elanco Animal Health. His extensive experience has made Potter familiar with the increasing food safety risks producers face.

“In this role, I’m hoping to collaborate with our poultry science department and industry to help reduce food safety risks such as Salmonella, Campylobacter and foreign material. Also, I am looking forward to helping processing plants optimize their operations,” Potter said. “From a research standpoint, I hope to help develop innovative biotechnologies and systems to help the poultry industry meet food safety and processing objectives.”

In addition to his research and extension duties, Potter plans to use his teaching assignment as a chance to “add some real-world practical knowledge to help mentor both younger students and develop industry professionals.”

Potter can be contacted directly at bdpotter@uada.edu or bdpotter@uark.edu or 479-575-2211.

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uada.edu. Follow on Twitter at @ArkAgResearch. To learn more about the Division of Agriculture, visit https://uada.edu/. Follow us on Twitter at @AgInArk. To learn about extension programs in Arkansas, contact your local Cooperative Extension Service agent or visit www.uaex.uada.edu.

Food safety scientists crank up steam, radio waves to kill salmonella amid spice recall

By Maddie Johnson
University of Arkansas System Division of Agriculture
Arkansas Agricultural Experiment Station

FAYETTEVILLE, Ark. — Bacteria can easily hibernate in low-moisture ingredients such as flour and spices, and food scientists have been working on ways to make them safer with novel technologies.

SPICE SAFETY — Surabhi Wason, Ph.D., used a combination of radiofrequency and steam to sanitize spices in packages while a doctoral student in the food science department. (U of A System Division of Agriculture photo)

Publication of a food safety study on radiofrequency pasteurization and novel steam technology highlights the recent national recall of black pepper for salmonella risk. The June 3 recall brought low-moisture foods to the forefront of public discussion, showing just because bacteria can’t grow well in dry foods doesn’t mean they don’t pose a threat.

Surabhi Wason was the lead author of the study titled “Radiofrequency inactivation of salmonella in black pepper and dried basil leaves using in-package steaming,” which was published in the Journal of Food Protection. She conducted experiments to develop in-package steaming for enhancing the efficiency of radiofrequency pasteurization of spices and evaluate its impact on the spice quality.

“Radiofrequency, also referred to as macrowave, is a long wavelength, non-ionizing electrical form of energy,” Wason said. “The significant application for radiofrequency technology is in the treatment of dry ingredients where microbes are considered dormant and are in the most difficult state to kill.”

Wason explained that the radiofrequency, or RF, generator creates an alternating electric field between two electrodes, causing the polar water molecules in the material to generate friction, which causes the material to heat rapidly and uniformly.

Wason is a former doctoral student of Jeyam Subbiah, head of the food science department, who served as corresponding author for the study. The food science department is encompassed both by the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture, as well as the Dale Bumpers College of Agricultural, Food and Life Sciences.

Rossana Villa Rojas, assistant professor of practice in the food science and technology department at the University of Nebraska-Lincoln, was a co-author of the study showing that radiofrequency pasteurization and novel steam technology can inactivate salmonella in low-moisture foods, including spices, without significantly compromising quality.

The findings were based on work supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 2020-67017-33256. McCormick & Company, Inc. supplied low-moisture food materials for the study.

How it works

When a salmonella is identified on a product quality testing, or during a foodborne illness outbreak, the industry has to recall all products since the last cleaning of the plant, Subbiah explained.

“Food processing plants that process low-moisture foods clean less frequently, often once a year, because water in the plant can increase food safety risks,” Subbiah said. “That means the industry has to recall several days to months of production, which could potentially mean that everything on the shelf, and thousands of other products that used that as an ingredient, have to recall, and it’s a huge financial loss. People don’t realize the magnitude of food safety.”

Under traditional methods, low-moisture foods must be exposed to high temperatures for long periods to kill bacteria. Salmonella and other pathogens like listeria can adapt to harsh environments and stay hidden for years, requiring severe processing to be killed, Subbiah said. Without inactivation, the pathogens can begin growing when met with ideal conditions, like the interaction with water that occurs when spices are used in soup.

Baby formula is another low-moisture food that can become dangerous when rehydrated. Subbiah said Cronobacter sakazakii contamination in baby formula can lead to severe illness and death for babies.

With traditional methods, severe heat treatment diminishes aspects of the food quality such as nutrient content and may damage the package because of the generation of steam, Subbiah said. Scientists can also pasteurize these foods through irradiation, or radiation exposure, but consumer acceptance is low, he added.

Subbiah found himself wondering whether the kind of packaging technology that is widely used for foods like microwavable vegetables could be adapted to allow for the same quick heating of dry foods with the additional step of resealing needed before their sale. To prevent steam buildup from eventually bursting packaging, experts developed a one-way valve that releases the steam and then reseals, which is at the heart of Subbiah’s study.

This new valve technology mimics the in-package sterilization of canned goods and uses radiofrequency heating. Conventional heating methods transfer heat to a product through its surface and take longer to reach the center, but radiofrequency heating generates heat inside an entire product mass evenly through friction generated by the vibrating water molecules in an electric field, much like microwave technology. This way, products are pasteurized while they are already in their final packaging and are heated uniformly, avoiding the risk of overheating the edges before heat reaches the center. This in-package processing cuts the risk of contamination that can occur when products are moved between the pasteurization and packaging stages, and foods are safe from contamination until customers open them.

“The gold standard is to package it in the final form and kill the bacteria, like canning,” Subbiah said.

“This technology shows promise for extending to other products like flour, cereal grains offering a robust solution for diverse food sectors," Wason added. "Moreover, one of the key advantages of radiofrequency pasteurization lies in its continuous processing capability. By implementing a conveyor belt system, products can move seamlessly through the RF chamber, ensuring consistent and efficient pasteurization.”

Sticky situation

Subbiah was first inclined to explore this topic of low-moisture food safety after witnessing the costs of a 2007 peanut butter recall.

QUALITY AND SAFETY — Jeyam Subbiah, head of the food science department, conducts research through the Arkansas Agricultural Experiment Station to improve food quality and retain safety. (U of A System photo)

Recalls for products such as packaged meat require consumers to avoid products processed on a specific day. With dry foods such as peanut butter, though, sanitation of production facilities may happen just once a year, or every few years, to avoid exposing the product to water. This means that in cases of recall, a years’ worth of product, and any other foods that feature it as an ingredient, might pose a health risk for consumers and a financial loss for producers.

The company ended up recalling all peanut butter produced as far back as January 2004, an expected loss of $50-60 million.

In addition to his work with the experiment station, Subbiah also collaborates with the Center for Low-Moisture Food Safety based out of Michigan State University, which includes a stakeholder advisory group of industry professionals that take work like Subbiah’s from the publication to real-world application phase.

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uada.edu. Follow on Twitter at @ArkAgResearch. To learn more about the Division of Agriculture, visit https://uada.edu/. Follow us on Twitter at @AgInArk. To learn about extension programs in Arkansas, contact your local Cooperative Extension Service agent or visit www.uaex.uada.edu.

Poultry science grad students earn awards for research presentations at international meeting

By Jessica Wesson
U of A System Division of Agriculture

FAYETTEVILLE, Ark. — Poultry vaccine research using a technique similar to allergy testing in humans and a project to discern the digestibility of phosphorus from meat and bone have earned two student scientists recognition at the International Poultry Scientific Forum.

CERTIFICATE OF EXCELLENCE — Chrysta Beck holds her Certificate of Excellence award at the International Poultry Scientific Forum in Atlanta. (U of A System Division of Agriculture photo)

Chrysta Beck and Jay Hampton, poultry science graduate students in the Dale Bumpers College of Agricultural, Food and Life Sciences at the University of Arkansas, were honored for sharing their research during the annual meeting Jan. 30-Feb. 1 in Atlanta.

Beck presented her research on the immune responses of chickens to Salmonella vaccine injections and received the Certificate of Excellence in the “Physiology, Endocrinology and Reproduction: Layers, Breeders” category by the Southern Poultry Science Society. Hampton’s mineral digestibility research presentation was awarded the Outstanding Graduate Student Research Presentation in the “Metabolism and Nutrition Category.”

Fighting Salmonella

“Poultry products are major contributors to human salmonellosis cases, and effective management of Salmonella during pre- and post-harvest is necessary to reduce human foodborne illness,” Beck said.

With a decline in the use of antibiotics in broilers, Salmonella vaccination programs are increasingly important, she said. According to a study conducted by the Food and Drug Administration and the U.S. Poultry and Egg Association, the use of antibiotics in broilers decreased from 90 percent in 2013 to zero percent in 2021.

While vaccination programs are largely successful, some may contribute to liver damage in poultry.

“Insight into the physiological responses to these vaccinations are necessary to improve the development and optimization of safe Salmonella vaccines that can enhance bird performance and quality of life,” Beck said.

To assess those responses, Beck injected dead Salmonella bacteria into skin tissues that produce feathers. This allowed her to determine local immune responses over time for a single animal.

“This method is similar to allergy skin tests and patch tests that are used in human medicine,” she said.

Her current study was conducted using Light-brown Leghorn pullet chickens and her next study will look at inflammatory responses to a commercial Salmonella vaccination in the liver, spleen and cecal tonsils, as well as the gut bacteria of White Leghorns.

While earning her bachelor’s and master’s degrees at Mississippi State University, Beck worked in a microbiology lab that studied the application of probiotics in broiler hatching eggs. She learned that bacteria-based vaccinations could shape the performance of a chick, which intrigued her.

“Because of this I wanted to be more competent in understanding the complexities of the avian immune system and how it connected to bird well-being and performance,” Beck said.

Gisela Erf, professor of poultry science, supervised Beck’s work. Erf conducts research for the University of Arkansas System Division of Agriculture through its research arm, the Arkansas Agricultural Experiment Station.

“I reached out to Dr. Erf, and she graciously welcomed me into her lab to grow in this field of research.”

Phosphorous Digestibility

OUTSTANDING RESEARCH — Jay Hampton, center, holds his award for Outstanding Graduate Student Research on phosphorus digestibility. Also pictured are Kyle Teague, left, and Benjamin Parsons.

Hampton’s research gauges how well poultry can digest the important mineral phosphorus.

“Traditionally, phosphorus is supplied in broiler diets through inorganic rock phosphates; however, recent publications estimate that these sources are dwindling,” Hampton said. “To this end, there is a need to establish phosphorus digestibility values from meat and bone meals as literature on these sources are limited — especially sourced from U.S. producers.”

The factors driving digestibility are unknown, and Hampton’s goal is to find the relationships between meat and bones and their characteristics.

Accurate values are important to poultry nutritionists “so phosphorus is adequately supplied as it is important for bird performance, health and maintaining animal welfare standards,” Hampton said.

“Meat and bone meals provide adequate levels of phosphorus and can be obtained from U.S. producers.”

Hampton’s research was supervised by Sam Rochell, associate professor of poultry nutrition at Auburn University and former assistant professor of poultry nutrition for the Arkansas Agricultural Experiment Station. Michael Kidd, professor of poultry nutrition for the University of Arkansas System, also assisted with the research.

“I would like to thank Dr. Rochell for all the help and guidance during graduate school,” Hampton said. “I also cannot say thank you enough to my fellow lab mates and Dr. Mike Kidd’s lab for helping collect samples during a hectic time. My current research will hopefully provide more insight into meat and bone meal digestibility values, and I am excited to present at future conferences.”

To learn about extension programs in Arkansas, contact your local Cooperative Extension Service agent or visit www.uaex.uada.edu. Follow us on Twitter and Instagram at @AR_Extension. To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uada.edu/. Follow on Twitter at @ArkAgResearch. To learn more about the Division of Agriculture, visit https://uada.edu/. Follow us on Twitter at @AgInArk.

New poultry science researcher plans to pursue foodborne pathogen control

By Jessica Wesson
Center of Excellence for Poultry Science
U of A System Division of Agriculture

FAYETTEVILLE, Ark. — Tomi Obe, new assistant professor with the Center of Excellence for Poultry Science and department of poultry science, is eager to find ways to identify and control foodborne pathogens in the poultry industry.

SAFE FOOD — Tomi Obe, assistant professor of poultry science, will focus on identification and control of foodborne illnesses in poultry. (U of A System Division of Agriculture photo by Fred Miller)

“I was introduced to poultry processing and food microbiology,” Obe said. “This attracted me to want to investigate Salmonella in poultry, and I have since dedicated my research to investigating Salmonella in poultry during live production and processing.”

Obe conducts research for the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture. She received her bachelor’s, master’s and Ph.D. degrees in poultry science — all from Mississippi State University.

While at Mississippi State University, Obe said she became interested in improving food safety in poultry and poultry products. Her current research focuses on understanding Salmonella and Campylobacter persistence in poultry production and processing environments.

Salmonella is a leading cause of bacterial foodborne illness in the United States. According to Obe, 1 in 6 human cases is linked to poultry. 

“Salmonella is very diverse with over 2,500 serotypes that are unique, and it has been a challenge for the industry to effectively prevent contamination of poultry products,” Obe said.

Serotypes are distinct types of Salmonella within subspecies of Salmonella species, and some forms of control may not work for all serotypes, she said.

Obe said she plans to build on her past research on Salmonella. At Mississippi State University, she tested how the bacteria adapted to stressors in poultry processing.

“I evaluated ways that Salmonella adapts to poultry processing-related stresses to acquire tolerance, persistence in processing environments and biofilm formation on food contact surfaces,” Obe said.

Biofilms are structures formed by microorganisms like Salmonella, she said, often as an adaptation to survive in less ideal conditions. Data from her previous research showed that Salmonella could persist on processing surfaces using different techniques, especially biofilm formation. Moving forward, her team will be bio-mapping Salmonella prevalence and quantity on food-contact surfaces and exploring ways to establish targeted mitigations for virulent serotypes.

The end goal, Obe said, is to improve control methods that will benefit the poultry industry in a practical way.

“Our goal is to use the information from our research to develop techniques to quickly identify virulent foodborne pathogens and establish targeted control strategies,” Obe said.

“We are very excited to have Dr. Tomi Obe join our program. She has an impressive background in researching the presence of foodborne pathogens in commercial poultry in both the production and processing environments,” said David Caldwell, director of the Center of Excellence for Poultry Science and poultry science department head. “We fully expect that Dr. Obe will make impactful contributions to our research, teaching, and outreach programs. She is a great addition to the faculty in our department and center.”

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: aaes.uada.edu. Follow us on Twitter at @ArkAgResearch. For information about the Cooperative Extension Service, visit www.uaex.uada.edu and follow us on Twitter at @AR_Extension. To learn more about the Division of Agriculture, visit uada.edu. Follow us on Twitter at @AgInArk.