A new Listeria monocytogenes outbreak associated with enoki mushroomshas sickened two people, both of whom were hospitalized. In the course of investigating this outbreak, Michigan state investigators found Listeria spp. in enoki mushrooms collected from the same store where one of the outbreak patients purchased mushrooms; however, the strain in this sample was different from the outbreak strain. Since 2020, enoki mushrooms have been linked to at least one outbreak and numerous recalls related to L. monocytogenes contamination.
The U.S. Salmonella Typhimurium outbreak announced on Nov. 16 that sickened at least 274 individuals was declared over by FDA. No food source for this outbreak has been identified.
Other outbreaks discussed in previous eNews reports that are now over include the Salmonella Litchfield outbreak associated with raw salmon, the E. coli O121:H19 outbreak associated with frozen falafel, and the L. monocytogenes outbreak associated with Brie and Camembert cheeses.
Numerous wild and domesticated birds across the U.S. continue to be infected with highly pathogenic avian influenza (HPAI) this month, although the number of confirmed detections appears to be declining. More birds have died this year (including those culled) as a result of HPAI than in any previous year.
Consumption of acai (the fruit of the acai palm tree) has been linked to at least nine cases of Chagas disease in Brazil. Chagas disease is caused by infection with the parasite Trypanosoma cruzi and can be difficult to diagnose. Other outbreaks of disease have previously been associated with acai or its juice. (Photo from Wikipedia)
Three probable cases of botulism recently have been identified in individuals who received cosmetic injections of botulinum toxin at a beauty salon in Jordan. This is not the first time that cosmetic injections of the toxin have been associated with botulism.
Government and Regulatory News
The Reagan-Udall’s expert panel has completed its external review of FDA’s human foods program. You can read the full report here. The panel’s many recommendations included changes in the area of culture, organizational structure (need for a central leader, elevate the human foods program within FDA), resources (more money and ability to recruit and maintain appropriate personnel), and authorities (to be bolder, less risk averse). For a more detailed summary of the recommendations and FDA’s initial response, go here and here.
FDA issued two guidance documents (one draft and one final) containing questions and answers regarding food allergen labeling requirements to help the food industry properly list any major food allergen on the labels of FDA-regulated foods. Comments about the draft guidance should be submitted before Jan. 30, 2023.
FDA published a recently completed systematic review on Food Safety Culture (FSC), concluding, “there is general consensus in the literature on how to define FSC…FSC is something beyond a procedural food safety management system…there is general agreement on the determinants of a strong and effective FSC: leadership; communication; commitment to food safety; risk awareness; environment; accountability; and employee knowledge, attitudes, behaviors, and values.”
USDA’s Deputy Under Secretary for Food Safety Sandra Eskin spoke recently about Salmonella, including USDA’s current and potential future positions regarding Salmonella as an adulterant in meat and poultry products. You can listen to the 30-minute podcast here.
FDA’s Center for Veterinary Medicine published the 2021 Summary Report on Antimicrobials Sold or Distributed for Use in Food-Producing Animals. This year’s report shows that domestic sales and distribution of medically important antimicrobial drugs approved for use in food-producing animals decreased by less than one percent between 2020 and 2021. Since the significant (~33%) decrease in sales volume in 2017, annual sales of medically important antimicrobials have remained at reduced levels. In 2017, such antimicrobials transitioned from OTC marketing to either prescription or Veterinary Feed Directive marketing status.
Current Literature
How much can processing treatments (thermal processes, extrusion, HPP, germination, fermentation, hydrolysis, etc.) reduce the allergenicity of nuts and legumes? A new meta-analysis found that protein extrusion and fermentation caused the greatest reductions (standard mean differences of about -0.2) in allergenicity, with most thermal processing treatments having little or no effect.
How do plant-based milks (PBM) compare to milk in terms of nutrition? A recent study found that only 11% of PBM (of >1,000 products in the USDA Branded Food Products Database) met nutrient standards for optimum energy, minimum protein content, maximum amounts for saturated fats and total sugars, and adequate fortification with calcium and vitamins A and D. Protein was the limiting nutrient for most products, with only soy- and pea protein-containing products matching the protein content of milk. On the plus side: Nearly all PBM met recommendations for sodium content.
At cold temperatures, fatty acids from the environment are incorporated into the membrane of Listeria, possibly to save the energy normally used for fatty acid synthesis, according to a new study. The types of fatty acids (unsaturated vs. saturated) present in the immediate environment have a significant impact on Listeria growth. The presence of unsaturated fatty acids promotes the growth of L. monocytogenes at 5°C (but not at 37°C). At 5°C, the unsaturated fatty acids are incorporated into the membrane of L. monocytogenes, increasing its fluidity (and compensating for the decrease in membrane fluidity caused by the lower temperature) and thereby allowing the organism to grow. In contrast, the incorporation of saturated fatty acids from its environment decreases membrane fluidity and prevents Listeria growth at 5°C.
Many natural substances found in foods have antimicrobial properties. A new review discusses one category that has not received a lot of attention: oligosaccharides, including those related to chitin, chitosan, pectin, and also fructo-oligosaccharides, milk oligosaccharides, alginate oligosaccharides, and more. The paper describes the known antimicrobial properties of these compounds, their mechanisms of action, and potential applications in the food industry.
In the summer of 2020, a Salmonella outbreak linked to onions occurred that eventually sickened more than 1,100 people in the U.S., with additional cases identified in Canada. CDC researchers have now published a detailed summary of this outbreak and its investigation. Traceback analysis identified a common onion grower in Bakersfield, Calif., but the outbreak strain was not identified in environmental samples at the grower, nor in product, despite extensive testing. The exact cause of the outbreak was not determined. The outbreak was notable for its large size (~10 times the size of other onion outbreaks) and the international data sharing that resulted in a rapid identification of red onions as the cause of the outbreak.
Why do humans eat spices? Do spices improve health, perhaps by improving food safety, or preventing a chronic disease such as cancer?A new article discusses these hypotheses and provides epidemiological and statistical evidence that suggests neither of these hypotheses is correct (but doesn’t present any other hypotheses).
Other News
The baguette is the latest entry to Representative List of the Intangible Cultural Heritage of Humanity of the United Nations Educational, Scientific and Cultural Organization (UNESCO). Will Wisconsin cheese curds be next on the list?
Is food tastier now than it was 40 years ago?And will it become less tasty in the future? Two interesting reads discuss the past and future of food, its taste, and its place in our culture:
For a humorous, non-scientific discussion of whether foods (especially holiday foods) are tastier now than in the past (and why, for such reasons as increased variety of ingredients, use of seasonal and local ingredients, and the abandonment of all things Jell-O), read here.
For a brief but moving sci-fi story on the importance of food culture and the power of food to bring people together (which imagines future food may be bio-engineered nutrient blocks in silver packets), read here.
Among the many fascinating chapters in “Candy Bites,” a book written by UW-Madison food science professor Rich Hartel and his daughter, AnnaKate Hartel, is one devoted to the candy cane, which is said to have been invented by a choirmaster in Cologne, Germany, to give to children in his choir to keep them quiet during long Christmas church services. Another entertaining chapter in the book investigates whether or not a Babe Ruth candy bar will float in a swimming pool…
FRI eNews will be on holiday hiatus until mid-January, when we'll bring you the latest FRI, UW, and food safety news and research.
A new Listeria monocytogenes outbreak associated with enoki mushrooms 
The U.S. Salmonella Typhimurium outbreak 
Consumption of acai (the fruit of the acai palm tree) 
Three probable cases of botulism recently 
The Reagan-Udall’s expert panel has completed its external review of FDA’s human foods program. You can read the full report 
USDA’s Deputy Under Secretary for Food Safety Sandra Eskin spoke recently about Salmonella, including USDA’s current and potential future positions regarding Salmonella as an adulterant in meat and poultry products. You can listen to the 30-minute podcast 
the significant (~33%) decrease in sales volume in 2017, annual sales of medically important antimicrobials have remained at reduced levels. In 2017, such antimicrobials 
How do plant-based milks (PBM) compare to milk in terms of nutrition? A 
Many natural substances found in foods have antimicrobial properties. A 
In the summer of 2020, a Salmonella outbreak linked to onions occurred that eventually sickened more than 1,100 people in the U.S., with additional cases identified in Canada. CDC researchers 
that resulted in a rapid identification of red onions as the cause of the outbreak.
The baguette is 
For a humorous, non-scientific discussion of whether foods (especially holiday foods) are tastier now than in the past (and why, for such reasons as increased variety of ingredients, use of seasonal and local ingredients, and the abandonment of all things Jell-O), read 
Among the many fascinating chapters in “
