Category Archives: Research

Research – Insight into Bacillus cereus Associated with Infant Foods in Beijing

Posted on March 5, 2022 by | Leave a comment

MDPI

This study was undertaken to investigate the prevalence, antimicrobial resistance, and virulence gene profiles of Bacillus cereus in different brands of infant formula in Beijing supermarkets. Eighty-eight Bacillus cereus isolates were recovered in sixty-eight infant formulas of five domestic brands and fourteen imported brands. The prevalence rate in domestic and imported samples were 70.6% and 52.9%, respectively. Lower mean prevalence level was found in domestic samples (1.17 MPN/g) compared with the imported samples (3.52 MPN/g). Twenty-four virulence gene profiles were found, and most strains carried at least one virulence gene. The prevalence of nheA, nheB, nheC, cytK, bceT, and entFM in domestic and imported brand samples was similar. The occurrence of enterotoxin genes hblA, hblC, and hblD in domestic samples were 22.2%, 27.8%, and 22.2%, respectively, which was significantly higher than imported samples. Antimicrobial drugs-susceptibility analysis showed that all isolates were susceptible to gentamincin, amikacin, and ciprofloxacin; 38%, 7%, and 2.3% were resistant to rifampin, tetracycline, and chloramphenicol, respectively; and only one isolate was resistant to trimethoprim-sulfamethoxazole. Moreover, the cell numbers of Bacillus cereus in prepared infant formula increased rapidly at room temperature. Thus, monitoring guidelines are needed for accepted levels of Bacillus cereus in infant formula.

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

Research – Genetic Diversity and Relationships of Listeria monocytogenes Serogroup IIa Isolated in Poland

Posted on March 5, 2022 by | Leave a comment

MDPI

In the present study, 100 L. monocytogenes isolates of serogroup IIa from food and food production environments in Poland were characterized towards the presence of virulence, resistance, and stress response genes using whole-genome sequencing (WGS). The strains were also molecularly typed and compared with multi-locus sequence typing (MLST) and core genome MLST analyses. The present isolates were grouped into 6 sublineages (SLs), with the most prevalent SL155 (33 isolates), SL121 (32 isolates), and SL8 (28 isolates) and classified into six clonal complexes, with the most prevalent CC155 (33 strains), CC121 (32 isolates), and CC8 (28 strains). Furthermore, the strains were grouped to eight sequence types, with the most prevalent ST155 (33 strains), ST121 (30 isolates), and ST8 (28; strains) followed by 60 cgMLST types (CTs). WGS data showed the presence of several virulence genes or putative molecular markers playing a role in pathogenesis of listeriosis and involved in survival of L. monocytogenes in adverse environmental conditions. Some of the present strains were molecularly closely related to L. monocytogenes previously isolated in Poland. The results of the study showed that food and food production environments may be a source of L. monocytogenes of serogroup IIa with pathogenic potential.

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

Research – Using lactic acid to control Salmonella in raw dog food

Posted on March 5, 2022 by | Leave a comment

Pet Food Processing

Can encapsulated and raw acidulants help to control Salmonella in raw meat-based dog foods? Samuel Kiprotich, a Ph.D. student at Kansas State University (KSU), presented his research on this topic at the American Feed Industry Association’s (AFIA) Pet Food Conference on Jan. 25, held in conjunction with International Production & Processing Expo (IPPE) in Atlanta, Ga.

Kiprotich noted that current methods of achieving kill steps for raw diets, such as high pressure pasteurization and irradiation, can be costly. The purpose of his study is to find a more inexpensive way to control foodborne pathogens, looking specifically at organic acids such as citric acid and lactic acids.

When incorporated into a raw meat-based pet food formula, organic acids can “shock” the product, causing discoloration and syneresis, Kiprotich explained. Encapsulating the organic acid, or coating it with edible vegetable oil, would allow it to be released more slowly into the product, “giving us the antimicrobial protection that we want without damaging the product,” he said.

Kiprotich’s study was conducted in two parts over a 22-day storage period: one to determine the efficacy of encapsulated and dry-plated lactic acids in controlling growth and survival of Salmonella enterica in a raw pet food, and another to monitor pH progression to measure acidity.

The experiment included two types of lactic acids — encapsulated and dry-plated — and three treatment levels for each acidulent: 1%, 2% and 3%. Two control diets formulated without acidulants were used, in which the positive control was inoculated with Salmonella, and the negative control was not inoculated.

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Posted in Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Pet Food, Pet Food Testing, raw pet food, Research, Salmonella, Salmonella Dog Food

Research – Contamination of Soil, Water, Fresh Produce, and Bivalve Mollusks with Toxoplasma gondii Oocysts: A Systematic Review

Posted on March 5, 2022 by | Leave a comment

MDPI

Toxoplas

Toxoplasma gondii is a major foodborne pathogen capable of infecting all warm-blooded animals, including humans. Although oocyst-associated toxoplasmosis outbreaks have been documented, the relevance of the environmental transmission route remains poorly investigated. Thus, we carried out an extensive systematic review on T. gondii oocyst contamination of soil, water, fresh produce, and mollusk bivalves, following the PRISMA guidelines. Studies published up to the end of 2020 were searched for in public databases and screened. The reference sections of the selected articles were examined to identify additional studies. A total of 102 out of 3201 articles were selected: 34 articles focused on soil, 40 focused on water, 23 focused on fresh produce (vegetables/fruits), and 21 focused on bivalve mollusks. Toxoplasma gondii oocysts were found in all matrices worldwide, with detection rates ranging from 0.09% (1/1109) to 100% (8/8) using bioassay or PCR-based detection methods. There was a high heterogeneity (I2 = 98.9%), which was influenced by both the sampling strategy (e.g., sampling site and sample type, sample composition, sample origin, season, number of samples, cat presence) and methodology (recovery and detection methods). Harmonized approaches are needed for the detection of T. gondii in different environmental matrices in order to obtain robust and comparable results.

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Posted in Contaminated water, food contamination, food handler, Food Hazard, Food Hygiene, Food Inspections, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Toxoplasma gondii, Toxoplasmosis, Water, water microbiology, Water Safety

Research – Antimicrobial Activity of Ohelo Berry (Vaccinium calycinum) Juice against Listeria monocytogenes and Its Potential for Milk Preservation

Posted on March 3, 2022 by | Leave a comment

MDPI

Listeria monocytogenes is a foodborne pathogen and causes illnesses with a high mortality rate in susceptible populations. Several dairy-related outbreaks have been attributed to contamination by L. monocytogenes, which requires antimicrobial interventions to enhance the safety of these products. This study aimed to determine the antimicrobial activity of the ohelo berry (Vaccinium calycinum), a Hawaiian wild relative of cranberry, against L. monocytogenes in culture media and milk products. The effect of ohelo berry juice at its sub-inhibitory concentrations on the physicochemical properties, biofilm formation, and gene expression of L. monocytogenes was also investigated. The minimum inhibitory concentration of ohelo berry juice against L. monocytogenes was 12.5%. The sub-inhibitory concentration of ohelo berry juice (6.25%) significantly increased the auto-aggregation and decreased the hydrophobicity, swimming motility, swarming motility, and biofilm formation capability of L. monocytogenes. The relative expression of genes for motility (flaA), biofilm formation and disinfectant resistance (sigB), invasion (iap), listeriolysin (hly), and phospholipase (plcA) was significantly downregulated in L. monocytogenes treated by the 6.25% juice. L. monocytogenes was significantly inhibited in whole and skim milk supplemented with 50% ohelo berry juice, regardless of the fat content. These findings highlight the potential of ohelo berry as a natural preservative and functional food to prevent L. monocytogenes infection.

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Posted in Biofilm, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Pathogen, Listeria, Listeria monocytogenes, Listeriolysin, microbial contamination, Microbiological Risk Assessment, Microbiology, Pathogen, pathogenic, Research

Research – Dietary Inclusion of a Saccharomyces cerevisiae-Derived Postbiotic Is Associated with Lower Salmonella enterica Burden in Broiler Chickens on a Commercial Farm in Honduras

Posted on March 3, 2022 by | Leave a comment

MDPI

Postbiotic feed additives may aid foodborne pathogen reduction during poultry rearing. The study objective was to evaluate a postbiotic additive in parallel to an industry control diet and the subsequent associated burden of Salmonella enterica on a single, commercial broiler farm in Honduras. Twelve houses were matched and assigned the standard diet (CON) or standard diet plus postbiotic (SCFP). New litter was placed in each house and retained across flock cycles with sampling prior to each chick placement and three consecutive rearing cycles. At ~33–34 days, 25 ceca were collected on-farm from each house, treatment, and cycle. Salmonella prevalence in litter for CON (30.6%) and SCFP (27.8%) were equivalent; however, Salmonella load within positive samples was lower (p = 0.04) for SCFP (3.81 log10 MPN/swab) compared to CON (5.53 log10 MPN/swab). Cecal prevalence of Salmonella was lower (p = 0.0006) in broilers fed SCFP (3.4%) compared to CON (12.2%). Salmonella load within positive ceca were numerically reduced (p = 0.121) by 1.45 log10 MPN/g for SCFP (2.41 log10 MPN/g) over CON (3.86 log10 MPN/g). Estimated burden was lower (p = 0.003) for SCFP flocks (3.80 log10 MPN) compared to CON (7.31 log10 MPN). These data demonstrate the preharvest intervention potential of postbiotics to reduce Salmonella enterica in broiler chickens. View Full-Text

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Posted in Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Saccharomyces cerevisiae, Salmonella, Salmonella in Chicken

Research – Finland and Switzerland see food recalls rise

Posted on March 3, 2022 by | Leave a comment

Food Safety News

Food recalls increased for the sixth year in a row in 2021, according to the Finnish Food Agency (Ruokavirasto).

The amount of alerts passed 300 for the first time and were mainly because of microbiological contamination, allergens and pesticide residues. The 309 recall total was 42 more than in 2020.

Microbiological concerns such as Salmonella, Listeria and other bacteria caused 49 recalls, which is up 9 percent compared to the previous year. Salmonella was behind 26 recalls in products including fresh herbs and eggs while Listeria in items such as cheese caused five recalls.

Switzerland has revealed the number of recalls and public warnings issued in 2020.

The Federal Food Safety and Veterinary Office (FSVO) published 28 public warnings and 49 recalls for food. Warnings were most often because of pesticide residues, pathogenic microorganisms or allergens. Recalls were mainly because of pesticide residues, foreign bodies or mycotoxins.

At the beginning of 2020, Swiss authorities were informed about norovirus in oysters and mussels from France. Eight other EU countries received mussels from affected French production sites. In Switzerland, illnesses occurred following consumption of these products.

A total of 241 RASFF notifications concerned Switzerland and 62 were issued by the country.

For the 241 notifications, almost a third related to pesticide residues and 27 were because of microbial contamination. Of notices raised by Switzerland, 15 were because of mycotoxins and pesticide residues caused eight. Fifteen products from Switzerland were the subject of a RASFF post. The most frequent hazard was microbial contamination with four notifications.

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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, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research, Salmonella

USA – FDA Warning Letter – Greenhead Lobster Products LLC

Posted on March 2, 2022 by | Leave a comment

FDA

The United States Food and Drug Administration (FDA) inspected your ready-to-eat (RTE) seafood processing facility located at 122 Heritage Park Rd., Bucksport, ME 04416-4603, on September 21, 22, 23, 27, and 30, and October 6, 2021. During our inspection we collected environmental samples (i.e., swabs) from various areas in your facility, including areas that are near food during processing operations and your food-contact surfaces. FDA laboratory analyses of environmental samples found the presence of Listeria monocytogenes (L. monocytogenes), a human pathogen, in your facility. Additionally, FDA found serious violations of the Seafood Hazard Analysis and Critical Control Point (HACCP) regulation, Title 21, Code of Federal Regulations (CFR), Part 123 (21 CFR Part 123).

In accordance with 21 CFR 123.6(g), failure of a processor of fish or fishery products to have and implement a HACCP plan that complies with this section or otherwise operate in accordance with the requirements of Part 123, renders the fish or fishery products adulterated within the meaning of Section 402(a)(4) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 342(a)(4). Based on our inspectional results, including review of FDA’s environmental testing and your HACCP plan, we have determined that your RTE cooked lobster products are adulterated within the meaning of section 402(a)(4) of the Act, 21 U.S.C. § 342(a)(4), in that they have been prepared, packed, or held under insanitary conditions whereby they may have become contaminated with filth or rendered injurious to health. You may find the Act, the seafood HACCP regulation, and the 4th Edition of the Fish and Fisheries Products Hazards and Controls Guidance through links in FDA’s home page at www.fda.gov.External Link Disclaimer

At the conclusion of the inspection, the FDA investigators issued your facility a Form FDA 483, Inspectional Observations. You provided responses to the FDA Form 483 and FDA’s environmental sample findings via email on October 7 and 13, 2021, which included corrective actions taken by your firm. We have reviewed the documentation and continue to have serious concerns with your current HACCP programs as further described in this letter.

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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, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research

Research – France – Acute gastroenteritis: results of winter surveillance 2019-2020

Posted on March 2, 2022 by | Leave a comment

Sante Publique

Food Borne Illness - Norovirus -CDC Photo

Public Health France publishes the 2019-2020 annual winter surveillance report for acute gastroenteritis in mainland France, marked by two major events and in particular a historic drop in AGEs never observed over the past 10 years. 

Acute winter gastroenteritis (AGE) is mainly of viral origin, with a dominant circulation of noroviruses and rotaviruses. Noroviruses are responsible for AGE in people of all ages, while rotaviruses mainly affect children under 5 years of age. A winter resurgence of cases is observed each year, in France, as in Europe, generating an increase in medical consultations for AGE usually between December and April. A peak is often observed during the first two weeks of January. 

Fluctuating activity for GEA over the 2019-2020 winter season

A significant peak observed in connection with an episode of collective food poisoning in several metropolitan areas

As in the two previous seasons, an increase in the number of AGE cases was observed at the start of the winter season, followed by a sharp increase in visits to hospital emergencies and general medicine at the end of December 2019 – beginning of January 2020, higher than the peaks of the 7 previous seasons in week 01-2020, and reaching 3.1% of total activity in hospital emergencies.

This upsurge in the number of AGE cases coincided with a significant and unusual occurrence of collective food poisoning that impacted several metropolitan areas in connection with the consumption of contaminated oysters that occurred in 2019* during the end-of-year celebrations. 

A sharp decrease in activity to historically low levels, most likely related to the measures put in place during the Covid-19 pandemic

Following the first confinement (March-April 2020) introduced as part of the Covid-19 pandemic , very low levels of activity for GEA were recorded from March and April 2020 in hospital emergencies and in general medicine (Sentinels Network and SOS Médecins).

Indeed, the proportion of emergency visits for gastroenteritis fell sharply at the start of 2020 to reach historically low levels and then stabilized at 0.5% of activity from April 2020 . According to data from the Sentinel Network, the 2019-2020 winter season was characterized by the lowest cumulative incidence rate of cases of acute diarrhea seen in general medicine consultations over the last 10 seasons .

This historic decrease in epidemic activity for acute gastroenteritis in France is most likely related to the measures introduced in the context of the COVID-19 pandemic (confinement, physical distancing, reinforcement of hand hygiene). Such levels have not been observed over 10 years of retrospective data for all monitoring indicators.

Key points 2019 – 2020 regarding acute gastroenteritis 

The analysis period corresponds to the winter monitoring period, from November 18, 2019 to April 13, 2020. 

  • 96,713 hospital emergency visits , i.e. 1.6% of emergency visits. 44.4% of visits for acute gastroenteritis concerned children aged under 5 years.
  • 144,499 SOS Médecins consultations for acute gastroenteritis, i.e. 8.7% of total consultations.
  • Cumulative incidence rate at the Sentinel Network: 
    • 2,963 cases per 100,000 inhabitants of all ages
    • 6,605 cases per 100,000 inhabitants, in children under 5 , the most affected population during this period.
  • Predominance of norovirus genotype GII.4 2012[P16], followed by genotype GII.17[P17].
  • Significant peak of activity observed at the end of December 2019-beginning of January 2020 , concomitant with a significant upsurge in collective food poisoning linked to the consumption of oysters
  • Following the first containment introduced as part of the Covid-19 pandemic, very low levels of activity were recorded from week 13-2020 

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Posted in Food Microbiology Research, Food Virus, gastroenteritis, Norovirus, Research, Rotavirus, Virus

USA – Updated Campylobacter Method

Posted on February 28, 2022 by | Leave a comment

USDA

USDA Food Safety and Inspection Service Microbiology Laboratory Guidebook Update

USDA Food Safety and Inspection Service sent this bulletin at 02/25/2022 08:00 PM EST

Microbiology Laboratory Guidebook for USDA Food Safety and Inspection Service. This method has recently been updated:

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Posted in Campylobacter, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Laboratory, Laboratory Method, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Research