Category Archives: Microbiology

UK – Happy Hounds recalls frozen raw dog food products due to the presence of Salmonella

FSA

 

Happy Hounds is recalling certain types of frozen raw dog food because salmonella has been found in the products.

Product details

Frozen Chicken & Beef Sleeve Dog Food

Pack size 1kg
Batch code 1205
Best before 3 September 2020
Frozen Chicken Mince Sleeve Dog Food

Pack size 1kg
Batch code 1205
Best before 3 September 2020
Frozen Chicken Mince Dog Food

Pack size 2.5kg (bag of 4)
Batch code 1205
Best before 3 September 2020

Risk statement

The presence of salmonella in the products listed above. Salmonella is a bacterium that can cause illness in humans and animals. The product could therefore carry a potential risk because of the presence of salmonella, either through direct handling of the pet food, or indirectly, for example from pet feeding bowls, utensils or contact with the faeces of animals.

In humans, symptoms caused by salmonella usually include fever, diarrhoea and abdominal cramps. Infected animals may not necessarily display signs of illness, but symptoms can include diarrhoea.

Action taken by the company

Happy Hounds is recalling the above products. Point of sale notices will be displayed in all retail stores that are selling these products. These notices explain to customers why the products are being recalled and tell them what to do if they have bought the product.

Our advice to consumers

Our advice to pet owners: If you have bought any of the above products do not use them. Instead, return them to the store from where they were bought for a full refund. When handling and serving raw pet food it is always advised to clean utensils and feeding bowls thoroughly after use. Consumers should wash hands thoroughly after handling raw pet food, bowls, utensils or after contact with the faeces of animals. Raw pet food should be stored separately from any food (especially ready to eat foods). Care should be taken when defrosting to avoid cross contamination of foods and surfaces.

Research – Prevalence of Salmonella in cucumbers, antibiotic and acid resistances and description of the kinetic behavior with dynamic model during storage

Wiley Online

This study isolated Salmonella from cucumbers, analyzed the antibiotic resistance and acid resistance for the isolates and developed a dynamic model. Salmonella prevalence in cucumbers and their resistances were determined. To describe the kinetic behavior of Salmonella isolates, the isolates were inoculated into cucumbers, and Salmonella cell counts were enumerated during storage at 10–30°C. The Baranyi model was fitted to the cell count data to calculate kinetic parameters (lag phase duration [LPD] and maximum specific growth rate (μmax)], and a polynomial model was fitted to the kinetic parameters as a function of temperature. The model performance was evaluated with root mean square error (RMSE). Using these models, a dynamic model was developed. Salmonella were detected in 3 of 24 cucumbers, all of which were multidrug‐resistant and one was acid‐resistant. As storage temperature increased, LPD decreased and μmax increased. These models were appropriate with 0.367 of RMSE. These results suggest that cross‐contaminated Salmonella could increase during transportation, and it may lead to human infection.

Research – Acidic environment could boost power of harmful pathogens

Science Daily

When food we’ve swallowed reaches our stomachs, it finds an acidic environment. The low pH in the stomach helps to begin digestion — and has been thought to kill the bacteria that hides in food that otherwise could harm our bodies.

However, recent work from the Ackley and Chandler labs in the Department of Molecular Biosciences at the University of Kansas runs counter to this idea, instead suggesting lower pH in the digestive tract may make some bacterial pathogens even more harmful.

Their findings, published in the peer-reviewed journal PLOS Pathogens, could have implications for addressing the crisis of antibiotic resistance in bacterial infections around the world.

The investigation was performed using small, bacteria-eating organisms called Caenorhabditis elegans.

Research – Treatment of fresh produce with a Salmonella‐targeted bacteriophage cocktail is compatible with chlorine or peracetic acid and more consistently preserves the microbial community on produce

Wiley Online

Diets rich in minimally processed foods are associated with numerous health benefits, in part, due to their diverse, natural microbiota. However, antimicrobials, such as chlorine and peracetic acid (PAA), that are used to address food safety concerns may damage the natural microflora of fresh produce. One promising approach for targeting pathogenic bacteria in foods without impacting the normal food microbiota are bacteriophages. In this study, we observed that combinational treatment of conventional antimicrobials (PAA and chlorine) and bacteriophages, specifically the Salmonella‐targeted preparation SalmoFresh, retained the bactericidal effectiveness of individual interventions, and in some cases, achieved substantially increased efficacy. Additionally, the bacterial microbiomes of farm fresh and organic produce were less affected after phage treatment compared to PAA and chlorine. Finally, our study revealed that resistance rates against SalmoFresh were relatively minor and unaffected by the stresses introduced after chemical washes and/or bacteriophage treatment.

Information -10 of the germiest places in hotel rooms

WFMZ

It’s the busiest travel time of the year. But before you pack up your suitcase and head to Grandma’s for the holidays, there’s something you should know about that hotel room you may be staying in: it’s dirtier than you think!

It looks clean, but just how clean is it?

Before you kick back your feet and turn on the TV, you might want to wipe down that remote with some Lysol wipes. These apparently house guests such as E. Coli, MRSA and Staph.

Be wary of the drinking glasses, especially if the hotel does not have a restaurant or a kitchen to wash the glasses. The habit of some cleaners is to rinse them under the bathroom tap without using soap and dry them with a hotel towel.

Some other tips: skip making your own coffee. Coffee makers can harbor mold and respiratory viruses if not cleaned properly.

And speaking of not being cleaned properly, one investigation of hotel ice buckets found many of them tested positive for E. coli.

Research-Nisin-Based Organic Acid Inactivation of Salmonella on Grape Tomatoes: Efficacy of Treatment with Bioluminescence ATP Assay

Journal of Food Protection

ABSTRACT

The antimicrobial activity of a new nisin-based organic acid sanitizer (NOAS), developed in our laboratory, was tested against viable aerobic mesophilic bacteria and Salmonella populations inoculated on produce surfaces. The activity of NOAS was compared with 200 ppm of chlorinated wash water and a bioluminescence ATP technique to determine the efficacy of treatments compared with plate count methods. The activity of the 10% final concentration of NOAS against viable populations of 109 CFU/mL Salmonella in phosphate-buffered saline (PBS), sterile deionized distilled water, and buffered peptone water was tested in vitro and on grape tomatoes inoculated with Salmonella at 2.5 log CFU/g. A similar batch of inoculated tomatoes were treated with 200 ppm of total available chlorinated water. All treatments for inactivation of viable Salmonella in vitro was tested up to 30 min and 5 min for the attached populations on tomatoes. Inactivation of viable Salmonella at 109 log CFU/mL by 10% the NOAS solution averaged >107 log CFU/mL in PBS, sterile deionized distilled water, and buffered peptone water. Similarly, Salmonella bacteria inactivated on tomato surfaces by the NOAS solution was significantly (P < 0.05) greater than numbers on chlorinated washed tomatoes, and surviving bacterial populations on NOAS and chlorine-treated tomatoes were <1 and 4 CFU/g, respectively. A significant linear correlation coefficient (r2 = 0.99) between the bioluminescence ATP assay and aerobic plate counts of inoculated and untreated grape tomatoes were recorded but not with NOAS and chlorine-treated tomatoes, as bacterial populations were less than the minimum baseline for determination. Also, the results indicated that the NOAS solution is a better alternative antimicrobial wash solution than 200 ppm of chlorinated water.

HIGHLIGHTS
  • The antimicrobial activity of NOAS was compared with chlorinated water.

  • Salmonella bacteria were more susceptible to NOAS than chlorinated water.

  • Assay correlated with aerobic plate count of inoculated and untreated tomatoes, not treated ones.

  • NOAS is an excellent alternative antimicrobial wash solution compared with chlorinated wash water.

Research – Inactivation of Murine Norovirus on Fruit and Vegetable Surfaces by Vapor Phase Hydrogen Peroxide

Journal of Food Protection

ABSTRACT

Vapor phase hydrogen peroxide (H2O2) can be utilized to inactivate murine norovirus (MNV), a surrogate of human norovirus, on surface areas. However, vapor phase H2O2 inactivation of virus on fruits and vegetables has not been characterized. In this study, MNV was used to determine whether vaporized H2O2 inactivates virus on surfaces of various fruits and vegetables (apples, blueberries, cucumbers, and strawberries). The effect of vapor phase H2O2 decontamination was investigated with two application systems. Plaque assays were performed after virus recovery from untreated and treated fresh produce to compare the quantity of infective MNV. The Mann-Whitney U test was applied to the test results to evaluate the virus titer reductions of treated food samples, with significance set at P ≤ 0.05. The infective MNV populations were significantly reduced on smooth surfaces by 4.3 log PFU (apples, P < 0.00001) and 4 log PFU or below the detection limit (blueberries, P = 0.0074) by treatment with vapor phase H2O2 (60 min, maximum of 214 ppm of H2O2). Similar treatments of artificially contaminated cucumbers resulted in a virus titer reduction of 1.9 log PFU. Treatment of inoculated strawberries resulted in 0.1- and 2.8-log reductions of MNV. However, MNV reduction rates on cucumbers (P = 0.3809) and strawberries (P = 0,7414) were not significant. Triangle tests and color measurements of untreated and treated apples, cucumbers, blueberries, and strawberries revealed no differences in color and consistency after H2O2 treatment. No increase of the H2O2 concentration in treated fruits and vegetables compared with untreated produce was observed. This study reveals for the first time the conditions under which vapor phase H2O2 inactivates MNV on selected fresh fruit and vegetable surfaces.

HIGHLIGHTS
  • Produce was treated with vapor phase H2O2 for 60 min (maximum of 260 ppm of H2O2).

  • A 4-log reduction in MNV was achieved by H2O2 treatment on apples and blueberries.

  • Reductions of MNV on treated strawberries and cucumbers were not significant.

Research- Survival Evaluation of Salmonella and Listeria monocytogenes on Selective and Nonselective Media in Ground Chicken Meat Subjected to High Hydrostatic Pressure and Carvacrol

Journal of Food Protection

ABSTRACT

High pressure processing (HPP) and treatment with the essential oil extract carvacrol had synergistic inactivation effects on Salmonella and Listeria monocytogenes in fresh ground chicken meat. Seven days after HPP treatment at 350 MPa for 10 min, Salmonella treated with 0.75% carvacrol was reduced to below the detection limit (1 log CFU/g) at 4°C and was reduced by ca. 6 log CFU at 10°C. L. monocytogenes was more sensitive to these imposed stressors, remaining below the detection limit during storage at both 4 and 10°C after HPP treatment at 350 MPa for 10 min following treatment with 0.45% carvacrol. However, pressure-injured bacterial cells may recover and lead to an overestimation of process lethality when a selective medium is used without proper justification. For HPP-stressed Salmonella, a 1- to 2-log difference was found between viable counts on xylose lysine Tergitol 4 agar and aerobic plate counts, but no significant difference was found for HPP-stressed L. monocytogenes between polymyxin–acriflavine–lithium chloride–ceftazidime–esculin–mannitol (PALCAM) agar and aerobic plate counts. HPP-induced bacterial injury and its recovery have been investigated by comparing selective and nonselective agar plate counts; however, few investigations have addressed this issue in the presence of essential oil extracts, taking into account the effect of high pressure and natural antimicrobial compounds (e.g., carvacrol) on bacterial survival in various growth media. Use of selective media may overestimate the efficacy of bacterial inactivation in food processing evaluation and validation studies, and the effects of various media should be systematically investigated.

HIGHLIGHTS
  • HPP and carvacrol had synergistic pathogen inactivation effects in ground chicken meat.

  • HPP at 350 MPa for 10 min with 0.60% carvacrol treatment resulted in a >5-log pathogen reduction.

  • A 1- to 2-log difference was found for counts of HPP-treated Salmonella on two growth media.

  • Counts of HPP-treated L. monocytogenes were similar on selective and nonselective media.

  • Carvacrol suppressed the growth and recovery of the HPP-treated bacterial cells.

Research -Inactivation of Bacillus cereus Spores on Stainless Steel by Combined Superheated Steam and UV-C Irradiation Treatment

Journal of Food Protection

ABSTRACT

Bacillus cereus spore contamination on food contact surfaces is of great concern in the food industry. Thus, in the present study, superheated steam (SHS) was used alone or combined with UV-C irradiation for inactivation of B. cereus spores inoculated on stainless steel coupons. Temperatures higher than 250°C were needed to effectively inactivate B. cereus spores by SHS treatment alone, while a synergistic bactericidal effect resulted from the sequential treatment of SHS before or after UV-C irradiation. The increased dipicolinic acid ratio obtained by the combined treatment had a significant role in the synergistic bactericidal effect. Therefore, the combined treatment of SHS and UV-C could be used effectively to inactivate B. cereus on stainless steel. It is recommended to use hurdle technology with reduced energy consumption to ensure microbiological safety on food contact surfaces.

HIGHLIGHTS
  • Inactivation of Bacillus cereus spores on stainless steel was identified in this study.

  • Superheated steam (SHS) was applied solely or combined with UV-C irradiation.

  • A synergistic effect was observed by combination treatment for spore inactivation.

  • The dipicolinic acid (DPA) release level increased significantly by combination treatment.

  • The combination treatment can be applied to sanitize food processing equipment.

RASFF Alerts – Animal Feed – Salmonella – Sunflower Seed Pellets – Soy Pellets – Fish Meal

RASFF-Logo

RASFF – Salmonella enterica ser. Senftenberg (presence /25g) in sunflower seed pellets from Ukraine, via the Netherlands in Belgium

RASFF – Salmonella enterica ser. Senftenberg (present /25g) in soy pellets from Italy in Belgium

RASFF – Salmonella enterica ser. Ohio (presence /25g) in fish meal from Denmark in Belgium