Category Archives: Microbiology Risk

Research – Natural preservatives for hams: Essential oil mixtures and major compounds’ efficacy against Clostridium sporogenes

Posted on September 9, 2023 by | Leave a comment

Wiley Online

Abstract

The demand for healthier products by consumers has prompted research into the use of essential oils (EOs), which are known for their antimicrobial properties. This study investigated the antimicrobial properties of EOs as a potential alternative to synthetic preservatives, specifically, cinnamon, clove, and oregano EOs, as well as their majority compounds (cinnamaldehyde, eugenol, and carvacrol) on Clostridium sporogenes inoculated in hams. The findings of the study revealed that cinnamon EO and its major compound cinnamaldehyde were the most efficient in inhibiting the growth of C. sporogenes, demonstrating the lowest minimum bactericidal concentration MBC (0.1%). The combination of oregano EO, cinnamon EO, cinnamaldehyde, and carvacrol led to a significant decrease in bacterial growth (approximately 3 log) after 28 days in hams. Furthermore, the presence of spores was not observed for 14 days (at 14°C) and 21 days (at 7°C) of storage, indicating a delay in sporulation. The treatments using the combination of EOs, and their major compounds had minimal impact on the color of the hams while maintaining the physicochemical characteristics of the product. This study demonstrates that EOs and their major compounds can be applied as natural preservatives in ham, offering a potential alternative for reducing the use of nitrites in various food types. The research emphasizes the antibacterial efficacy of cinnamon, clove, and oregano EOs, along with their major compounds, in inhibiting C. sporogenes in ham. The findings indicate that these natural alternatives could be valuable in preserving food products and reducing the reliance on synthetic preservatives.

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Posted in Clostridium, Clostridium sprogenes, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

Research – Viability and Virulence of Listeria monocytogenes in Poultry

Posted on September 9, 2023 by | Leave a comment

MDPI

Abstract

The prevalence of Listeria monocytogenes in 30 samples of poultry was determined using culture-dependent (isolation on OCLA and confirmation by conventional polymerase chain reaction -PCR-, OCLA&PCR) and culture-independent (real-time polymerase chain reaction, q-PCR) methods. L. monocytogenes was detected in 15 samples (50.0%) by OCLA&PCR and in 20 (66.7%) by q-PCR. The concentrations (log10 cfu/g) of L. monocytogenes (q-PCR) ranged from 2.40 to 5.22 (total cells) and from <2.15 to 3.93 (viable cells). The two methods, q-PCR using a viability marker (v-PCR) and OCLA&PCR (gold standard), were compared for their capacity to detect viable cells of L. monocytogenes, with the potential to cause human disease. The values for sensitivity, specificity and efficiency of the v-PCR were 100%, 66.7% and 83.3%, respectively. The agreement between the two methods (kappa coefficient) was 0.67. The presence of nine virulence genes (hlyA, actA, inlB, inlA, inlC, inlJ, prfA, plcA and iap) was studied in 45 L. monocytogenes isolates (three from each positive sample) using PCR. All the strains harbored between six and nine virulence genes. Fifteen isolates (33.3% of the total) did not show the potential to form biofilm on a polystyrene surface, as determined by a crystal violet assay. The remaining strains were classified as weak (23 isolates, 51.1% of the total), moderate (one isolate, 2.2%) or strong (six isolates, 13.3%) biofilm producers. The strains were tested for susceptibility to a panel of 15 antibiotics. An average of 5.11 ± 1.30 resistances per isolate was observed. When the values for resistance and for reduced susceptibility were taken jointly, this figure rose to 6.91 ± 1.59. There was a prevalence of resistance or reduced susceptibility of more than 50.0% for oxacillin, cefoxitin, cefotaxime, cefepime ciprofloxacin, enrofloxacin and nitrofurantoin. For the remaining antibiotics tested, the corresponding values ranged from 0.0% for chloramphenicol to 48.9% for rifampicin. The high prevalence and level of L. monocytogenes with numerous virulence factors in poultry underline how crucial it is to follow correct hygiene procedures during the processing of this foodstuff in order to reduce the risk of human listeriosis.

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Posted in Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Listeria, Listeria monocytogenes, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

South African scientists sound warning after Listeria found in beef

Posted on September 8, 2023 by | Leave a comment

Food Safety News

South African researchers have warned about the risk of another outbreak after a study found Listeria in the beef sector.

The study was conducted by scientists at the University of Pretoria (UP) in 2019 and 2020 into the prevalence of Listeria monocytogenes in beef and beef products at abattoirs and retailers in the Gauteng, Mpumalanga and North West provinces.

It showed that 4.6 percent of chilled carcasses sampled at seven abattoirs in Gauteng were positive for Listeria. This means that contaminated items could enter the food chain as beef products sold at retail outlets in the province.

The study, funded by Red Meat Research and Development South Africa, was prompted by the 2017-2018 outbreak of listeriosis with 1,065 confirmed cases and 218 deaths. It was traced to a ready-to-eat processed meat product called polony, made at a plant in Polokwane run by Enterprise Foods, which at that time was owned by Tiger Brands.

Ready-to-eat (RTE) food, including polony, were also positive for Listeria in the current study.

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Posted in Food Micro Blog, Food Microbiology, Food Microbiology Research, Food Microbiology Testing, Listeria, Listeria monocytogenes, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

FAO and WHO plan meeting on foodborne viruses

Posted on September 7, 2023 by | Leave a comment

Food Safety News

The UN Food and Agriculture Organization (FAO) and World Health Organization (WHO) are set to hold an expert meeting on viruses in food later this month.

The Joint FAO/WHO Expert Meeting on Microbiological Risk Assessment (JEMRA) event, at FAO headquarters in Rome on Sept. 18 to 22, will work on food attribution, analytical methods, and indicators of viruses in foods.

United States-based experts proposed for the meeting are Donald Schaffner, of Rutgers University; Xiang-Jin Meng, at Virginia Tech; Kali Kniel, from the University of Delaware; Lee-Ann Jaykus, at North Carolina State University; and Jacquelina Williams-Woods of the FDA.

In 2022, the Codex Committee on Food Hygiene (CCFH) asked JEMRA to provide scientific advice to inform a review of guidelines established in 2012. This was due to emerging issues associated with foodborne viruses and scientific developments.

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Posted in Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Virus, Food Virus Death, Hepatitis A, Hepatitis E, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Norovirus, Norovirus Oysters, Virus

Research – Essential Oils and Their Combination with Lactic Acid Bacteria and Bacteriocins to Improve the Safety and Shelf Life of Foods: A Review

Posted on September 6, 2023 by | Leave a comment

MDPI

Abstract

The use of plant extracts (e.g., essential oils and their active compounds) represents an interesting alternative to chemical additives and preservatives applied to delay the alteration and oxidation of foods during their storage. Essential oils (EO) are nowadays considered valuable sources of food preservatives as they provide a healthier alternative to synthetic chemicals while serving the same purpose without affecting food quality parameters. The natural antimicrobial molecules found in medicinal plants represent a possible solution against drug-resistant bacteria, which represent a global health problem, especially for foodborne infections. Several solutions related to their application on food have been described, such as incorporation in active packaging or edible film and direct encapsulation. However, the use of bioactive concentrations of plant derivatives may negatively impact the sensorial characteristics of the final product, and to solve this problem, their application has been proposed in combination with other hurdles, including biocontrol agents. Biocontrol agents are microbial cultures capable of producing natural antimicrobials, including bacteriocins, organic acids, volatile organic compounds, and hydrolytic enzymes. The major effect of bacteriocins or bacteriocin-producing LAB (lactic acid bacteria) on food is obtained when their use is combined with other preservation methods. The combined use of EOs and biocontrol agents in fruit and vegetables, meat, and dairy products is becoming more and more important due to growing concerns about potentially dangerous and toxic synthetic additives. The combination of these two hurdles can improve the safety and shelf life (inactivation of spoilage or pathogenic microorganisms) of the final products while maintaining or stabilizing their sensory and nutritional quality. This review critically describes and collects the most updated works regarding the application of EOs in different food sectors and their combination with biocontrol agents and bacteriocins.

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Posted in Decontamination Microbial, essential oils, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Safety, Food Safety Management, lactic acid bacteria, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

Research – Evaluation of Hygiene Practice for Reducing Campylobacter Contamination on Cutting Boards and Risks Associated with Chicken Handling in Kitchen Environment

Posted on September 6, 2023 by | Leave a comment

MDPI

Abstract

Campylobacter kswfoodworld

Cutting boards can serve as potential carriers for the cross-contamination of pathogens from chicken to other surfaces. This study aimed to assess chefs’ handling practices of cutting boards across five provinces in China and identify the key factors contributing to unsafe cutting board usage, including cleaning methods and handling practices. Handling practices associated with cutting boards were examined through a web-based survey (N = 154), while kitchen environment tests were conducted to investigate the splashing or survival of Campylobacter, inoculated in chicken or on cutting boards, to mimic the practices of chefs. Among chefs in the five provinces of China, wood and plastic cutting boards were the most commonly used for preparing chicken meat. Approximately 33.7% of chefs washed boards with running tap water, 31.17% of chefs washed boards with detergent, and 24.03% of chefs cleaned boards by scraping them with a knife after preparing other meats or chicken. The study tested 23 cutting boards from commercial kitchens for Campylobacter presence before and after chicken preparation and cleaning. Among these, 17 were cleaned with a knife, 5 with running tap water, and only 1 with disinfectant. Results showed that cleaning with a knife significantly reduced Campylobacter presence on cutting boards (p < 0.05), while the three main cleaning methods were inadequate in eliminating contamination to a safe level. In kitchen environment tests, contaminated chicken was chopped on cutting boards, with a maximum distance of 60 cm for low contamination, and 120 cm for medium and high contamination levels. This suggested a contamination risk exposure area ranging from 60 cm to 120 cm. Campylobacter survival on surfaces of wood, plastic, and stainless steel was also tested, with plastic surfaces showing the longest survival time (4.5 h at 15 °C and 3.5 h at 25 °C) In comparison, survival time on stainless steel or wood surfaces was only 3 h, implying a cross-contamination risk exposure period of 3 to 4.5 h after chicken preparation. In conclusion, based on the current study data, the practices employed by chefs play an important role in Campylobacter transfer in the kitchen environment. The presence of Campylobacter on cutting boards even after wiping or droplet splashing highlights its potential as a source of cross-contamination in the kitchen environment. So, chefs in China should reinforce their hygiene culture and adopt effective cutting board cleaning practices to prevent pathogen contamination.

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Posted in Campylobacter, campylobacter coli, Campylobacter jejuni, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

Research – Utilization of Algae Extracts as Natural Antibacterial and Antioxidants for Controlling Foodborne Bacteria in Meat Products

Posted on September 6, 2023 by | Leave a comment

MDPI

Abstract

Padina pavonica, Hormophysa cuneiformis, and Corallina officinalis are three types of algae that are assumed to be used as antibacterial agents. Our study’s goal was to look into algal extracts’ potential to be used as food preservative agents and to evaluate their ability to inhibit pathogenic bacteria in several meat products (pastirma, beef burger, luncheon, minced meat, and kofta) from the local markets in Alexandria, Egypt. By testing their antibacterial activity, results demonstrated that Padina pavonica showed the highest antibacterial activity towards Bacillus cereus, Staphylococcus aureus, Escherichia coli, Streptococcus pyogenes, Salmonella spp., and Klebsiella pneumoniae. Padina pavonica extract also possesses most phenolic and flavonoid content overall. It has 24 mg gallic acid equivalent/g and 7.04 mg catechol equivalent/g, respectively. Moreover, the algae extracts were tested for their antioxidant activity, and the findings were measured using ascorbic acid as a benchmark. The IC50 of ascorbic acid was found to be 25.09 μg/mL, while Padina pavonica exhibited an IC50 value of 267.49 μg/mL, Corallina officinalis 305.01 μg/mL, and Hormophysa cuneiformis 325.23 μg/mL. In this study, Padina pavonica extract was utilized in three different concentrations (Treatment 1 g/100 g, Treatment 2 g/100 g, and Treatment 3 g/100 g) on beef burger as a model. The results showed that as the concentration of the extract increased, the bacterial inhibition increased over time. Bacillus cereus was found to be the most susceptible to the extract, while Streptococcus pyogenes was the least. In addition, Padina pavonica was confirmed to be a safe compound through cytotoxicity testing. After conducting a sensory evaluation test, it was confirmed that Padina pavonica in meat products proved to be a satisfactory product.

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Posted in Antibacterial, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

Research – Reoccurring Escherichia coli O157:H7 Strain Linked to Leafy Greens–Associated Outbreaks, 2016–2019

Posted on September 6, 2023 by | Leave a comment

CDC

Abstract

Genomic characterization of an Escherichia coli O157:H7 strain linked to leafy greens–associated outbreaks dates its emergence to late 2015. One clade has notable accessory genomic content and a previously described mutation putatively associated with increased arsenic tolerance. This strain is a reoccurring, emerging, or persistent strain causing illness over an extended period.

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Posted in Decontamination Microbial, E.coli O157, E.coli O157:H7, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, STEC, STEC E.coli

Research – Cyclospora cayetanensis: A Perspective (2020–2023) with Emphasis on Epidemiology and Detection Methods

Posted on September 6, 2023 by | Leave a comment

MDPI

Abstract

Cyclospora cayetanensis infections are prevalent worldwide, and the parasite has become a major public health and food safety concern. Although important efforts have been dedicated to advance toward preventing and reducing incidences of cyclosporiasis, there are still several knowledge gaps that hamper the implementation of effective measures to prevent the contamination of produce and water with Cyclospora oocysts. Some of these data gaps can be attributed to the fact that access to oocysts is a limiting factor in C. cayetanensis research. There are no animal models or in vivo or in vitro culture systems to propagate the oocysts needed to facilitate C. cayetanensis research. Thus, researchers must rely upon limited supplies of oocysts obtained from naturally infected human patients considerably restricting what can be learnt about this parasite. Despite the limited supply of C. cayetanensis oocysts, several important advances have happened in the past 3 years. Great progress has been made in the Cyclospora field in the areas of molecular characterization of strains and species, generation of genomes, and development of novel detection methods. This comprehensive perspective summarizes research published from 2020 to 2023 and evaluates what we have learnt and identifies those aspects in which further research is needed.

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Posted in Contaminated water, Cyclospora, Cyclosporiasis, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Parasite, Protozoan, Water, water microbiology, Water Safety

USA – Mid America Pet Food Issues Voluntary Recall Due to Possible Salmonella Health Risk

Posted on September 5, 2023 by | Leave a comment

FDA

Victor Super Premium Dog Food, Hi-Pro Plus, Net Wt. 5 lbs, front label

Company Announcement

Mid America Pet Food, Mount Pleasant, Texas, is voluntarily recalling one lot of Victor Super Premium Dog Food, Hi-Pro Plus produced at its Mount Pleasant, Texas production facility because it has the potential to be contaminated with Salmonella. Salmonella can affect animals eating the products and there is risk to humans from handling contaminated pet products, especially if they have not thoroughly washed their hands after having contact with the products or any surfaces exposed to these products.

Healthy people infected with Salmonella should monitor themselves for some or all of the following symptoms: nausea, vomiting, diarrhea or bloody diarrhea, abdominal cramping and fever. Rarely, Salmonella can result in more serious ailments, including arterial infections, endocarditis, arthritis, muscle pain, eye irritation, and urinary tract symptoms. Consumers exhibiting these signs after having contact with this product should contact their healthcare providers.

Pets with Salmonella infections may be lethargic and have diarrhea or bloody diarrhea, fever, and vomiting. Some pets will have only decreased appetite, fever and abdominal pain. Infected but otherwise healthy pets can be carriers and infect other animals or humans. If your pet has consumed the recalled product and has these symptoms, please contact your veterinarian.

The affected product was only sold in 5-pound bags. No human or pet illnesses have been reported to date.

Products were distributed to various distributors and retailers in the United States. The affected product consists of 644 cases sold in 5-pound bags with lot code 1000016385 with Best By Date 4/30/2024. Lot code information is found on the back of the bag. Images of product are below.

No other products are included in this recall.

This voluntary recall is being issued due to a single sample of Victor Super Premium Dog Food that tested positive for Salmonella in a random sample test conducted by the South Carolina Department of Agriculture.

Retailers and distributors should immediately pull the recalled lot from their inventory and shelves. Do not sell or donate the recalled products.

Do not feed the recalled product to pets or any other animals. Destroy the food in a way that children, pets and wildlife cannot access. Wash and sanitize pet food bowls, cups and storage containers. Always ensure you wash and sanitize your hands after handling recalled food or any utensils that come in contact with recalled food.

Contact Mid America Pet Food Consumer Affairs at info@mapf.com or 1-888-428-7544 from 8 AM to 5 PM Central Time, Monday through Friday for additional information.
This is a voluntary recall being conducted in cooperation with the U.S. Food and Drug Administration.

Company Contact Information

Consumers:
Mid America Pet Food Consumer Affairs
 1-888-428-7544
 info@mapf.com
Media:
Tim Schramm
 908-370-4771

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Posted in Food Micro Blog, Food Microbiology Blog, microbial contamination, Microbial growth, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Pet Food, Pet Food Salmonella, Pet Food Testing, Salmonella Dog Food