Category Archives: Research

Researchers pioneer nanotechnology to combat E. coli in rice, strengthen food safety

Food Safety News

Researchers at the University of Texas at El Paso (UTEP) have made a major breakthrough in agricultural biotechnology, focusing on the use of nanotechnology to combat E. coli contamination in rice crops. This discovery, led by Hamidreza Sharifan and his team, offers promising solutions for improving food safety and addressing bioterrorism threats.

The research centers on the development of advanced methods to detect and mitigate the effects of pathogens, particularly E. coli, which poses a significant threat to global food systems. The team, which includes Daisy Wilson, a Ph.D. student in environmental science and engineering, and Valeria Gonzalez, a senior undergraduate in forensic science, conducted groundbreaking work in biofortification and nanoparticle application to reduce microbial contamination.

“We got an internship with the Department of Homeland Security as a team,” Wilson told The Prospector, UTEP’s student newspaper. “It was led by Dr. Sharifan, and he mentored myself and Valeria for the summer.”

Research – Listeria in Pregnancy—The Forgotten Culprit

MDPI

Listeria monocytogenes is a Gram-positive bacterium that causes listeriosis, a severe foodborne illness that is particularly dangerous during pregnancy. It thrives in diverse environments, including refrigerated conditions and food production facilities, due to its adaptability to varying temperatures, pH levels, and salt concentrations. Its virulence stems from the ability to invade host cells, particularly macrophages and epithelial cells, and avoid, or at least postpone, immune detection by utilizing virulence factors such as internalins, listeriolysin O, and actin assembly-inducing protein. This intracellular motility and biofilm formation make LM a persistent pathogen in food safety and public health. Pregnant women are at a much higher risk of listeriosis, which can result in serious fetal complications such as miscarriage, stillbirth, and preterm labor due to LM’s affinity for placental tissues. The vertical transmission of LM from mother to fetus can lead to neonatal listeriosis, which can result in sepsis and meningitis, with high mortality rates if not promptly treated. Early diagnosis and treatment with antibiotics, such as ampicillin or gentamicin, are crucial for maternal and neonatal outcomes.

Research – Is it possible to reduce foodborne Campylobacter infections in humans through vaccination of animals?

Science Direct

Vaccination has been used successfully over the years to eradicate many serious diseases, but what about human foodborne pathogens, such as Campylobacter? Most human cases of Campylobacter infection are associated with consumption of poultry products. Vaccination of poultry to prevent early colonization or to reduce the Campylobacter colonization level may be a viable intervention strategy in the future; however, no commercial Campylobacter vaccine is currently available.

Research – Impact of Various Washing Protocols on the Mitigation of Escherichia coli Contamination in Raw Salad Vegetables

MDPI

Vegetables are an essential component of a balanced diet. The consumption of ready-to-eat foods may lead to the risk of infections and illnesses due to microbial contamination. To mitigate the potential of microbial contamination risks, it is critical to promote safe handling practices among consumers. In this study, our research evaluated the efficacy of different vegetable washing methods, specifically with lettuce, tomato, and cucumber, to establish optimal practices for reducing microbial contamination. This study consisted of two phases. Initially, a survey was distributed to 150 volunteers using snowball sampling to assess everyday vegetable handling and washing methods. The survey’s results identified four predominant methods: washing with a 5% vinegar solution for 3 min followed by tap water rinse (37.3% of participants), rinsing with tap water for 1 min (29.3%), washing with a 5% salt solution (vegetable soap) for 3 min followed by a tap water rinse (16.6%), and a 3 min tap water rinse (14%). A minor segment (3.33%) reported not washing their vegetables at all. The survey’s findings guided the second phase, which tested the aforementioned washing protocols’ effectiveness in reducing Escherichia coli (E. coli) levels on spiked contaminated salad vegetables. The tested vegetables were sterilized using UV light, inoculated with 0.5 McFarland E. coli, and then washed using the four identified methods. After that, E. coli enumeration after washing was performed using 3M™ Petrifilm and the comparison was analyzed via one-way ANOVA. During this study, it was revealed that the cucumbers had the highest E. coli contamination levels in comparison to the lettuce and tomato after washing. Interestingly, by comparing the three washing methods, it was found that washing the vegetables with vinegar proved to be the most effective solution for reducing microbial presence on both lettuce and cucumbers. Notably, the natural smoothness of tomato skin led to no significant differences in contamination levels across washing methods. In summary, vinegar washing effectively reduces microbial contamination from salad vegetables, highlighting the need for informed consumer practices to prevent foodborne outbreaks. This study emphasizes the importance of monitoring contamination sources and using safe washing techniques.

Research – E. coli in Food

MAST

In light of the news of the last few days, the Swedish Food Agency considers it appropriate to emphasize several points regarding the handling of food, especially with E. coli in mind.

What is E. coli ?

There are many types of coliform bacteria. They are found in the intestines of humans and animals. Some species can produce toxins and thus cause serious diseases in people, especially children, the elderly and other vulnerable individuals. These toxin-producing E. coli bacteria are called STEC (Shiga Toxin-producing Escherichia Coli ) and can cause serious illness in some cases.

Foodborne infections due to E. coli

The bacteria can get into meat during slaughter, if the contents of the animal’s intestines come into contact with the meat. Preventive measures that reduce the chance of meat becoming contaminated are therefore important, such as clean tools and hygiene during slaughter. The bacteria can also get into vegetables, fruits and other things that are grown in close contact with soil, organic waste or water that is contaminated with feces.

People can become infected with E. coli , through contaminated food (tdhakki and vegetables) or water, through direct contact with animals or environments contaminated with their feces. The bacterium thus gets through the mouth and down into the digestive tract.

It is common practice that beef, lamb and horse steaks are served without being deep-fried. On raw pieces of meat, bacteria are on the outer layer of the meat and not inside the muscle. They are therefore killed when the meat is fried or grilled at high temperatures. Everything else applies to hamburgers and other dishes made from minced meat. When meat is minced, microorganisms spread throughout the meat. Light frying therefore does not kill bacteria present in the meat. In order to kill E. coli and other disease-causing microorganisms, the hamburgers and other mincemeat dishes must be fried through or so that the core temperature is at least 75°C.

What can consumers do to avoid infection?

  • Fully fry round hamburgers and other minced meat
  • Maintain kitchen hygiene when handling raw and minced meat
  • Avoid cross contamination by keeping meat separate from other foods, especially from those that should not be cooked such as salad
  • Rinse all vegetables in clean water
  • Wash cutting boards, utensils, knives and the surrounding area after handling raw meat to prevent the transfer of bacteria to foods that are not to be heated
  • Do not wipe up blood with a cloth used on other surfaces, use paper towels instead
  • Good hand washing with soap and water after using the toilet, before handling food and after handling raw meat is an important rule to prevent infection
  • Prevent blood from leaking from meat in the fridge
  • Avoid consumption of unpasteurized dairy products

Irish Seafood Agency Reveals Major Incidents in 2023

Food Safety News

An Irish agency responsible for seafood safety has published its annual report, revealing the number of food safety incidents investigated in 2023.

The Sea-Fisheries Protection Authority (SFPA) was involved in 25 reports of alleged illnesses following the consumption of fishery products or live bivalve mollusks.

Sea-Fisheries Protection Officers (SFPOs) carried out 2,297 food safety official controls across 2,325 premises. Of these checks, 535 were inspections of approved establishments, and 1,553 consisted of official controls, such as checks prior to certifying a consignment of food being exported to a non-EU country and temperature and labeling checks.

Research – Best Practices for Handling Raw Flour: Raw Flour has been Linked to Salmonella and E. coli Outbreaks

Food Poisoning News

A common ingredient found in most kitchens, raw flour is a key ingredient in many delicious recipes. However, that uncooked flour can harbor harmful bacteria such as Escherichia coli (E. coli) and Salmonella, posing significant health risks to consumers.

Contrary to popular belief, most flour is typically a raw agricultural product that has not undergone treatment to eliminate pathogens. The milling process, including grinding and bleaching, does not kill these harmful microorganisms, which can taint grain in the field or during flour production.

Multiple outbreaks linked to raw flour or cake mix have made national news in recent years, including incidents in 2016, 2019, 2021, and 2023. Some of these investigations resulted in product recalls, such as the 2019 recall over E. coli-contaminated raw flour from Pillsbury, King Arthur, and Aldi, highlighting the ongoing potential danger of consuming this food.

According to one food safety expert, “Consumers should be aware that flour has a long shelf life, and products purchased even years ago could still pose a risk. We recommend checking for any recalled flour or baking mixes and discarding them immediately.”

Read more at the link above.

Research – Evaluating Chlorine Sanitization at Practical Concentrations for Controlling Listeria monocytogenes and Salmonella on Fresh Peaches

MDPI

Abstract

Recent foodborne outbreaks and recalls involving Listeria monocytogenes and Salmonella-contaminated peaches have caused significant economic losses to the peach industry. This study evaluated the effectiveness of chlorine, a commonly used sanitizer in the fresh produce industry, against L. monocytogenes and Salmonella and its ability to control cross-contamination in fresh peaches. Peaches inoculated with L. monocytogenes or Salmonella (~6 log10 CFU/peach) were treated with 50–150 mg/L of free chlorine (FC, pH6.8) 24 h post-inoculation. The results revealed that chlorine had similar efficacy against L. monocytogenes and Salmonella on peaches (p > 0.05). A 30 s treatment at 50, 100, and 150 mg/L FC resulted in dose-dependent reductions (p < 0.05), achieving reductions of 0.88–0.92, 1.54–1.61, and 1.73–1.79 log10 CFU/peach, respectively. Extending the contact time to 2 min slightly but significantly enhanced the chlorine efficacy (p < 0.05). Additionally, a 30 s to 2 min exposure to chlorine with 50–150 mg/L FC resulted in a 1.05–1.43 log10 CFU/peach reduction in yeasts and molds. Tap water exposure led to substantial cross-contamination between inoculated and uninoculated fruits and processed water, with Salmonella exhibiting higher transfer rates than L. monocytogenes. The application of chlorine mitigated the cross-contamination of both pathogens but did not entirely prevent it. These findings offer valuable insights for the peach and other stone fruit industries to verify process controls.

Research – Fortification of Orange and Apple Juices with Ferulic Acid: Implications for Food Safety and Quality

MDPI

Abstract

In recent years, the awareness of healthier lifestyles among consumers has driven to an increased interest in more natural, nutritious, and low-processed foods. Ferulic acid, one of the most abundant phenolic acids in plants, has demonstrated a wide spectrum of antimicrobial activities and a range of biomedical effects, including antioxidant, antiallergic, hepatoprotective, anticarcinogenic, anti-inflammatory, and antithrombotic, among others. The objective of this work was to study the antilisterial effect of ferulic acid (FA, 1500 mg/L) on fresh, ready-to-eat orange (FOJ) and apple (FAJ) juices and evaluate its effect on product quality. The results showed that FA reduced the Listeria monocytogenes population after 9 days of storage at 4 °C, but no effect on the indigenous microbiota was observed. The titratable acidity and color significantly changed. The antioxidant capacity and total phenolic content significantly increased with the addition of FA, being at least two times greater in fortified juices. FAJ and FOJ containing FA were scored lower (6.8 and 5.7 on a 9-point hedonic scale, respectively) than their respective controls. Overall, our results demonstrated that FA treatment could be a useful strategy to maintain the safety of fresh apple and orange juices and increase the antioxidant activity and phenolic content. The potential industrial applications and health benefits of the fortification of fruit juices with FA should be further explored.

Research – Innovative Pathogen Reduction in Exported Sea Bass Through Atmospheric Cold Plasma Technology

MDPI

Abstract

The safety of sea bass is critical for the global food trade. This study evaluated the effectiveness of atmospheric cold plasma in reducing food safety risks posed by Salmonella Enteritidis and Listeria monocytogenes, which can contaminate sea bass post harvest. Cold plasma was applied to inoculated sea bass for 2 to 18 min, achieving a maximum reduction of 1.43 log CFU/g for S. Enteritidis and 0.80 log CFU/g for L. monocytogenes at 18 min. Longer treatments resulted in greater reductions; however, odor and taste quality declined to a below average quality in samples treated for 12 min or longer. Plasma treatment did not significantly alter the color, texture, or water activity (aw) of the fish. Higher levels of thiobarbituric acid reactive substances (TBARSs) were observed with increased exposure times. Cold plasma was also tested in vitro on S. Enteritidis and L. monocytogenes on agar surfaces. A 4 min treatment eliminated the initial loads of S. Enteritidis (2.71 log CFU) and L. monocytogenes (2.98 log CFU). The findings highlight the potential of cold plasma in enhancing the safety of naturally contaminated fish. Cold plasma represents a promising technology for improving food safety in the global fish trade and continues to be a significant area of research in food science.