Category Archives: Food Microbiology Research

USA – CDC – Salmonella in Peanut Butter – Investigation Details

CDC

CDC, public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) are collecting different types of data to investigate a multistate outbreak of Salmonella Senftenberg infections.

Epidemiologic and laboratory data show that some Jif brand peanut butters may be contaminated with Salmonella Senftenberg and are making people sick.

Epidemiologic Data

As of May 21 2022, a total of 14 people infected with the outbreak strain of Salmonella Senftenberg have been reported from 12 states (see map). Illnesses started on dates ranging from February 17, 2022, through May 1, 2022 (see timeline).

Sick people range in age from less than one to 85 years, with a median age of 56, and 71% are female. Of 6 people with information available, 2 have been hospitalized. No deaths have been reported.

The true number of sick people in an outbreak is likely much higher than the number reported, and the outbreak may not be limited to the states with known illnesses. This is because many people recover without medical care and are not tested for Salmonella. In addition, recent illnesses may not yet be reported as it usually takes 2 to 4 weeks to determine if a sick person is part of an outbreak.

State and local public health officials are interviewing people about the foods they ate in the week before they got sick. Of the five people interviewed, five (100%) reported eating peanut butter. Four of five (80%) sick people reported Jif brand peanut butter. Two people reported Jif Creamy Reduced Fat peanut butter, one person reported Jif Natural Creamy Low Sodium peanut butter, and one person reported Jif Natural Creamy peanut butter. This suggests that people in this outbreak got sick from eating peanut butter.

Laboratory Data

Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. CDC PulseNet manages a national database of DNA fingerprints of bacteria that cause foodborne illnesses. DNA fingerprinting is performed on bacteria using a method called whole genome sequencing (WGS). WGS showed that bacteria from sick people’s samples are closely related genetically. This suggests that people in this outbreak got sick from the same food.

WGS analysis shows that samples from sick people in this investigation are closely related genetically to a sample collected in 2010 from the environment at J.M. Smucker Company’s facility in Lexington, KY, where some Jif brand peanut butter is produced.

WGS analysis of bacteria from 14 people’s samples did not predict resistance to any antibiotics. Standard antibiotic susceptibility testing by CDC’s National Antimicrobial Resistance Monitoring System (NARMS) laboratory is currently underway.

Public Health Actions

On May 20 2022, J.M. Smucker Company recalledexternal icon multiple Jif brand peanut butter types. Do not eat, sell, or serve recalled Jif brand peanut butter.

Research – Microbial Consortium Associated with Crustacean Shells Composting

MDPI

Soil microbes play an essential role in the biodegradation of crustacean shells, which is the process of sustainable bioconversion to chitin derivatives ultimately resulting in the promotion of plant growth properties. While a number of microorganisms with chitinolytic properties have been characterized, little is known about the microbial taxa that participate in this process either by active chitin degradation or by facilitation of this activity through nutritional cooperation and composting with the chitinolytic microorganisms. In this study, we evaluated the transformation of the soil microbiome triggered by close approximation to the green crab shell surface. Our data indicate that the microbial community associated with green crab shell matter undergoes significant specialized changes, which was reflected in a decreased fungal and bacterial Shannon diversity and evenness and in a dramatic alteration in the community composition. The relative abundance of several bacterial and fungal genera including bacteria FlavobacteriumClostridiumPseudomonas, and Sanguibacter and fungi MortierellaMycochlamys, and Talaromyces were increased with approximation to the shell surface. Association with the shell triggered significant changes in microbial cooperation that incorporate microorganisms that were previously reported to be involved in chitin degradation as well as ones with no reported chitinolytic activity. Our study indicates that the biodegradation of crab shells in soil incorporates a consortium of microorganisms that might provide a more efficient way for bioconversion. View Full-Text

Research – Microbial Safety and Sensory Analyses of Cold-Smoked Salmon Produced with Sodium-Reduced Mineral Salts and Organic Acid Salts

MDPI

Cold-smoked (CS) salmon contains high levels of sodium salts, and excess dietary sodium intake is associated with an array of health complications. CS salmon may also represent a food safety risk due to possible presence and growth of the foodborne pathogen Listeria monocytogenes which may cause fatal human infections. Here we determine how reformulated CS salmon using commercial sodium-reduced salt replacers containing KCl (e.g., Nutek, Smart Salt, SOLO-LITE) and acetate-based preservative salts (Provian K, proviant NDV) affect sensory properties, quality, and microbial safety. Initial sensory screening of sodium-reduced CS salmon was followed by L. monocytogenes growth analyses in selected variants of reformulated CS salmon, and finally by analyses of CS salmon variants produced in an industrial smokehouse. Projective mapping indicated overall minor sensory changes in sodium-replaced samples compared with a conventional product with NaCl. Growth of L. monocytogenes was temperature-dependent (4 °C vs. 8 °C storage) with similar growth in sodium-reduced and conventional CS salmon. The addition of 0.9% of the preservative salts Provian K or Provian NDV gave up to 4 log lower L. monocytogenes counts in both sodium-reduced and conventional cold-smoked salmon after 29 days of chilled storage. No changes in pH (range 6.20–6.33), aw levels (range 0.960–0.973), or weight yield (96.8 ± 0.2%) were evident in CS salmon with salt replacers or Provian preservative salts. Analyses of CS salmon produced with selected mineral salt and preservative salt combinations in an industrial salmon smokery indicated marginal differences in sensory properties. Samples with the preservative salt Provian NDV provided L. monocytogenes growth inhibition and low-level total viable counts (<2.8 log/g) dominated by Photobacterium and Carnobacterium during storage. Production of sodium-reduced CS salmon with inhibiting salts provides a simple method to achieve a healthier food product with increased food safety.

Research – Removal of Ochratoxin A from Grape Juice by Clarification: A Response Surface Methodology Study

MDPI

This study achieved maximum removal of ochratoxin A (OTA) during the grape juice clarification process with minimal reduction in antioxidant compounds (phenolic acid, flavonoids, and antioxidant capacity by FRAP) by the RSM method. Independent variables included three types of clarifiers—gelatin, bentonite, and diatomite (diatomaceous earth)—at a concentration level of 0.25–0.75% and clarification time of 1–3 h. OTA was measured by high-performance liquid chromatography with fluorescence detection. Clarifying agent concentration and clarification time affected the reduction amount of OTA and antioxidant compounds in grape juice. There was a direct linear correlation between the reduction amounts of OTA and antioxidant compounds and capacity with the concentration of bentonite, gelatin, and diatomite, and the clarification time. The reduction amount of OTA and antioxidant capacity followed the linear mode. However, the decreased phenolic acid and flavonoid values followed the quadratic model. The study results showed that if the concentrations of bentonite, gelatin, and diatomite and clarification time were 0.45, 0.62, 0.25%, and 1 h, respectively, the maximum amount of OTA reduction (41.67%) occurred. Furthermore, the phenolic acid, flavonoid, and antioxidant activity decrease amounts were at their lowest levels, i.e., 23.86, 7.20, and 17.27%, respectively. View Full-Text

Research – Influence of Metal Concentration and Plumbing Materials on Legionella Contamination

MDPI

Legionella colonization of water supply pipes is a significant public health problem. The objective of this work was to evaluate Legionella colonization in hotel hot water systems and to investigate the relationship between metal concentrations, piping materials (galvanized iron pipes and plastic pipes), and Legionella proliferation. Concentrations of calcium and magnesium ions and the presence of Legionella pneumophila were determined in a total of 108 water samples from the hot water systems of four hotels in Split-Dalmatia County over a 12-month period, and additional data on piping materials were collected. L. pneumophila was isolated in 23.1% of all samples—in 28.8% (15/52) of water samples from galvanized iron pipes and in 17.8% (10/56) of samples from plastic pipes. L. pneumophila serogroups 2–14 were isolated from all samples. This study found higher prevalence of L. pneumophila at higher concentrations of Ca and Mg ions (except for Mg and plastic pipes). The metal parts of the water supply may be important factors in Legionella contamination due to the possibility of lime scale or roughness of the pipes. Higher Ca and Mg ion concentrations increased the risk of Legionella colonization. View Full-Text

USA – FSIS Issues Public Health Alert for Ready-To-Eat Ham Product Due to Possible Processing Deviation

FSIS USDA

The U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS) is issuing a public health alert for ready-to-eat (RTE) ham product because the product may not be fully cooked due to underprocessing. FSIS is issuing this public health alert to ensure that consumers are aware that this product should not be consumed. A recall was not requested because it is believed that the product is no longer available for consumers to purchase.

The RTE, sliced Black Forest Ham item was produced by Plumrose USA, doing business as Swift Prepared Foods, a Council Bluffs, Iowa establishment, from April 28, 2022 through May 1, 2022. The following product is subject to the public health alert [view labels]:

  • 1-lb resealable plastic packages containing “Great Value Black Forest Ham Water Added” with a “BEST IF USED BY 07/15/22” date.

The product subject to this public health alert bears establishment number “EST. 26C” inside the USDA mark of inspection. This item was shipped to Walmart stores in Illinois, Indiana and Ohio.

The problem was discovered when the firm identified product that did not appear to be fully cooked, which prompted the establishment to perform an investigation and notify FSIS of their findings that the ham was underprocessed.

There have been no confirmed reports of adverse reactions due to consumption of these products. Anyone concerned about an injury or illness should contact a healthcare provider.

FSIS is concerned that some product may be in consumers’ refrigerators or freezers. Consumers who have purchased these products are urged not to consume them. These products should be thrown away or returned to the place of purchase.

Members of the media with questions about the public health alert can contact Nikki Richardson, Head of Communications, Swift Prepared Foods, at nikki.richardson@jbssa.com. Consumers with questions about the public health alert can contact Rusty Parker, Strategic Accounts Manager, Swift Prepared Foods, at 479-268-7131.

Click to access PHA-05182022-Labels.pdf

USA – FDA Issues Final Guidance for Seeds Used for Sprouting

FDA

Constituent Update

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May 13, 2022

Today the U.S. Food and Drug Administration (FDA) issued a final guidance titled “Reducing Microbial Food Safety Hazards in the Production of Seed for Sprouting: Guidance for Industry.” This guidance outlines FDA’s serious concerns over foodborne illness outbreaks associated with the consumption of raw and lightly-cooked sprouts and provides firms with recommended steps to prevent adulteration throughout the production chain of seed for sprouting.

Between 1996 and 2020, there were 52 reported outbreaks of foodborne illness associated with contaminated sprouts, resulting in more than 2,700 cases of illness. Although contamination can occur at any point along the sprout supply chain, seed has historically been, and continues to be, identified as the likely source of contamination in many of these outbreaks. The Produce Safety Rule (PSR) includes sprout-specific requirements for sprout growers. However, we do not consider seed for sprouting to be covered produce under the PSR and, therefore, the growing, conditioning, and distribution of seed for sprouting is not subject to PSR requirements. Although seed used for sprouting is not covered by the PSR, the FDA does consider seed used for sprouting to be food.

The final guidance recommends that everyone in the sprout seed supply chain become as informed as reasonably possible about the food safety practices, processes, and procedures followed by the firm(s) from which they source their seed, where the seed will go after it leaves their firm, and whether their seed is reasonably likely to be used to produce sprouts for human consumption. The final guidance acknowledges that the practices and conditions appropriate for producing seed for sprouting likely will necessitate a higher level of food safety precautions compared to practices and conditions for producing seed that will be used for other purposes.

Consistent with the draft guidance published in June 2019, this final guidance recommends that seed for sprouting be grown using Good Agricultural Practices or in conformance with international standards such as the Codex Alimentarius International Code of Hygienic Practice for Fresh Fruits and VegetablesExternal Link Disclaimer. In addition, this guidance clarifies that testing should not be used in place of GAPs or Codex standards.

France – Prosecutors open criminal inquiry into French STEC E. coli outbreak linked to Nestlé pizza

Food Safety News

French authorities have stepped up their investigations related to an E. coli outbreak in the country linked to pizzas made by Nestlé.

The latest figures from Santé publique France show 56 cases and two deaths from Buitoni brand Fraîch’Up pizzas.

The Paris prosecutor’s office opened a criminal inquiry into the incident this past week. Charges include the involuntary manslaughter of one person, the injuring of 14 others and marketing a product dangerous to health.

An investigation had already been launched on March 22 and searches of the Nestlé factory in Caudry took place, authorized by the public health department of the Paris prosecutor’s office, on April 13.

A judicial inquiry is led by an investigating judge and was opened at the request of the public prosecutor to carry out such a highly complex investigation.

More than 50 children sick
Of the 56 infections, 54 were caused by E. coli O26 and two by E. coli O103, according to Santé publique France, the country’s public health agency.

USA – Bring Food Safety to Your Summer Vacation

FSIS USDA

As summertime brings families and friends together for outdoor celebrations, the U.S. Department of Agriculture (USDA) wants to make sure your summer festivities are food safe. Whether you’re grilling burgers, camping, or having a picnic, everyone should always remember to practice proper handwashing and use a food thermometer.

After observing that consumer behavior in test kitchens revealed that people are skipping basic food safety practices, USDA is concerned that consumers are not doing enough to reduce the risk of foodborne illness.

“Our research shows that participants were not adequately washing their hands or using a food thermometer,” says USDA Deputy Under Secretary for Food Safety Sandra Eskin “Summer is a time to relax and enjoy delicious meals with friends and family but foodborne pathogens never rest. Following safe food handling practices during this and all other seasons can reduce the risk of you and your loved ones getting sick.”

USDA encourages all Americans to follow these food safety tips to keep you and your family foodborne illness free this summer.

Wash Your Hands

Inadequate handwashing is a contributing factor to many illnesses, including foodborne illness. It is important to follow proper handwashing steps before, during, and after preparing food to prevent bacteria from transferring from your hands to your meal.

Recent USDA consumer research (January 2020-2021) showed that 56% of participants didn’t attempt to wash their hands during meal preparation. This is a major drop in handwashing attempts from prior years’ research. In year 3, this figure was 71% and in year 2 it was 74%.

In addition to low attempts at handwashing, roughly 95% of participants failed to wash their hands properly. The most common reason in the study for unsuccessful handwashing was failing to rub hands with soap for at least 20 seconds, followed by not wetting hands with water as a first step.

There are five steps for proper handwashing: wet hands, lather with soap, scrub for 20 seconds, rinse, and dry.

Use a Food Thermometer

Don’t forget to bring a food thermometer to your summer activities. Always use a food thermometer to check the internal temperature of your food to determine if it is safe to eat. Insert the thermometer into the thickest part of the meat, through the side, for the most accurate temperature reading. In the study, only 55% of participants used a food thermometer to check the internal temperature of the hamburgers and sausages they were cooking. Use a food thermometer to ensure the following foods have reached their safe internal temperature:

  • Beef, pork, lamb and veal steaks, chops and roasts: 145 F with a 3-minute rest
  • Fish: 145 F
  • Egg dishes: 160 F
  • Ground meats (beef, pork, lamb and veal): 160 F
  • All poultry (whole or ground): 165 F

Avoid Cross-Contamination

While preparing your meal this Memorial Day, be sure to keep your raw meat separate from your fruits and vegetables. Raw meat and poultry can carry bacteria that causes foodborne illness. To reduce the risk of cross-contamination, USDA recommends using separate cutting boards: one for raw meat and poultry, and another for fruits and vegetables.

In this study, cross-contamination was prevalent. Across all participants:

  • 32% contaminated their plates and cutting boards while preparing food.
  • 28% contaminated their kitchen sinks.
  • 12% contaminated spice containers.
  • 8% contaminated the cupboard handles in their kitchen.

These findings are part of a multi-year, mixed-method study that USDA’s Food Safety and Inspection Service (FSIS) commissioned to evaluate various consumer food handling behaviors. The study uses test kitchens, focus groups, and nationally representative surveys to better understand food safety practices and experiences with food recalls, foodborne illness, and FSIS food safety resources. More information about this study is available in an executive summary.

Research – An Exploration of Listeria monocytogenes, Its Influence on the UK Food Industry and Future Public Health Strategies

MDPI

Listeria monocytogenes is a Gram-positive intracellular pathogen that can cause listeriosis, an invasive disease affecting pregnant women, neonates, the elderly, and immunocompromised individuals. Principally foodborne, the pathogen is transmitted typically through contaminated foods. As a result, food manufacturers exert considerable efforts to eliminate L. monocytogenes from foodstuffs and the environment through food processing and disinfection. However, L. monocytogenes demonstrates a range of environmental stress tolerances, resulting in persistent colonies that act as reservoirs for the reintroduction of L. monocytogenes to food contact surfaces and food. Novel technologies for the rapid detection of L. monocytogenes and disinfection of food manufacturing industries have been developed to overcome these obstacles to minimise the risk of outbreaks and sporadic cases of listeriosis. This review is aimed at exploring L. monocytogenes in the UK, providing a summary of outbreaks, current routine microbiological testing and the increasing awareness of biocide tolerances. Recommendations for future research in the UK are made, pertaining to expanding the understanding of L. monocytogenes dissemination in the UK food industry and the continuation of novel technological developments for disinfection of food and the food manufacturing environment View Full-Text