Key Findings: 

This study conducted by the Nestlé research group proposes and validates a modified extraction protocol specific for testing infant formula and oil for cereulide contamination.¹

• Matrix complexity dictates extraction efficiency: The dense, low-moisture, lipid- and protein-rich structure of powdered infant formula sequesters cereulide within the matrix, reducing the efficiency of the acetonitrile-based extraction specified in ISO 18465. Direct extraction from powder yielded recoveries ranging from 4–13% (mean 7%). In contrast, performing the ISO 18465 procedure after an initial water reconstitution step resulted in ~100% recovery (n = 27, CV = 10%).
• Partitioning (“salting-out”) extraction markedly improves recovery: A QuEChERS-based water/acetonitrile partitioning approach significantly enhanced extraction efficiency, achieving high recoveries (~94.9–106.5%) of cereulide from powdered infant formula matrices.
• Improved limits of quantification with the revised protocol: 
  • 0.1 µg/kg for powdered infant formula and oils
  • 0.01 µg/kg for liquid formula
• These performance characteristics meet newly established requirements derived from the European Food Safety Authority (EFSA) acute reference dose (ARfD) for cereulide (0.0014 µg/kg body weight/day in infants), corresponding to an action threshold of 0.054 µg/L in reconstituted infant formula.

• Strong analytical robustness: The revised method demonstrated excellent analytical performance, including strong reproducibility, with repeatability and intermediate precision values below 17.7%, supporting suitability for routine analytical application.

Bigger Picture:

Detection reliability depends as much on extraction chemistry as on instrument sensitivity. For cereulide surveillance in powdered infant formula, optimized matrix-specific extraction is essential to ensure reliable risk assessment. The work provides compelling evidence that the ISO 18465:2017 method should not be applied to unmodified powdered infant formula and that the enhanced partitioning/salting out approach yields accurate and operationally efficient routine measurement for regulatory and quality assurance programs.

References:

1. Dubois et al. 2026. Determination of Cereulide by LC-MS/MS Requires Partitioning/Salting-out Extraction with Water/Acetonitrile for a Reliable Measurement in Powdered Infant Formula. Journal of AOAC INTERNATIONAL. In press.

Key Findings: 

The two studies evaluated the impact of Bifidobacterium longum ssp. infantis strain EVC001 on necrotizing enterocolitis (NEC) in preterm infants. In the first study, EVC001 was administered enterally to infants ≤33 6/7 weeks gestation until 36 weeks postmenstrual age; 265 infants received EVC001 and 277 did not.¹ In the second study, a retrospective, non-concurrent cohort study, 733 very low birth weight (VLBW, <1500 g) infants, including a subgroup of extremely low birth weight (ELBW, < 1000 g) infants, were evaluated before, during, and after routine probiotic administration, which was discontinued following regulatory caution.² Findings from these two studies are as follows: 

• Probiotic use was associated with reduced NEC ≥ stage 2 (p = 0.0058), decreased incidence of bloody stools (P < 0.0001), faster achievement of full enteral feeds (from 4.7 to 0.4% of days, P < 0.0001), and fewer total parenteral nutrition days (P < 0.0001).¹
• In VLBW infants, NEC incidence decreased from 7.7% in the untreated group to 0.9% in the probiotic group (P = 0.012).¹
• NEC incidence was lowest during EVC001 administration (2.6%) compared with pre-probiotic (12%) and post-probiotic cessation periods (16%).²
• NEC risk was significantly higher both pre-EVC001 (adjusted relative risk [aRR] 4.4, 95% CI 2.2–9.0) and post-EVC001 (aRR 4.5, 95% CI 2.0–9.9; P < 0.001) compared with the EVC001 period.²
• Severe NEC was less common in infants receiving EVC001 (VLBW OR 5.3, ELBW OR 5.0).²
• NEC-related mortality was lowest during EVC001 administration (0.9% vs 2.8% without EVC001).²

Bigger Picture:

Necrotizing Enterocolitis (NEC) remains one of the most feared complications of prematurity, with mortality rates that can exceed 20–30% in severe cases and long-term morbidity among survivors. Historically, NEC prevention strategies have focused on:

• Human milk feeding
• Antibiotic stewardship
• Improved NICU hygiene
• Feeding protocols

References:

1. Sohn et al. 2024. Bifidobacterium longum subsp infantis (EVC001) is Associated with Reduced Incidence of Necrotizing Enterocolitis Stage ≥2 and Bloody Stools in Premature Babies. Journal of Perinatology.  

2. Selesner et al., 2026. Increase in Necrotizing Enterocolitis with Cessation of Bifidobacterium longum ssp. infantis Administration in Very Low Birthweight Infants: A Single Center Retrospective Cohort Study. Journal of Pediatrics.

Key Findings: 

Yang et al. have used a well characterized the emetic Bacillus cereus strain, F4810/72, to define toxin production under environmental conditions with practical implications for the food industry.¹

Temperature is the Dominant Driver of Cereulide Production: Room-temperature abuse conditions remain the dominant driver for toxin production.

• Toxin production was fastest at ambient temperatures, particularly 25–30 °C, under favorable moisture and pH conditions.
• Production was suppressed at near 45 °C.

pH Influences Toxin Initiation Timing: pH does not just affect growth; it also regulates toxin production.

• Acidification to pH 5.0 delayed detectable cereulide production by approximately 6 hours compared with neutral conditions. 
• Neutral to slightly alkaline conditions supported more rapid toxin formation.

Water Activity Strongly Modulates Production: Moist foods represent significantly higher risk environments.

• High water activity accelerated cereulide synthesis.
• Water activity below 0.945 severely suppressed toxin production, significantly extending lag time.

Bigger Picture:

This study reflects an important shift in food safety modeling—from predicting bacterial growth alone to predicting toxin production kinetics. Notably, the environmental conditions that permit growth are not always identical to those that support toxin synthesis, making toxin-focused modeling particularly valuable. From a risk-management standpoint, these results reinforce that temperature abuse remains the single most critical driver of cereulide risk, but also demonstrate that pH and water activity interventions can act synergistically to delay or suppress toxin formation. More broadly, this work strengthens the case for quantitative predictive microbiology as a foundation for HACCP validation, shelf-life modeling, and risk-based process design. Instead of relying solely on empirical safety margins, food producers can use mechanistic models to identify environmental thresholds that prevent toxin formation, enabling more precise and defensible safety controls.

References:

1. Yang et al. 2026. Modelling Cereulide Production of Bacillus cereus Under Different Temperature, pH, and Water Activity Conditions. Food Microbiology. 

Key Findings: 

This study by Fenske et al. integrated retailer in-stock data, national sales trends, and consumer survey responses to characterize the 2022 shortage and recovery.¹

• Sharp decline in availability: National infant formula in-stock rates declined from approximately 78.6% in early 2022 to a low of ~27.6% in May 2022, marking the peak of the shortage. 
• Regional variability persisted: Recovery was geographically uneven, with significant state-to-state variability lasting for nearly one year before stabilizing in mid-2023. 
• Sales surges preceded shortages: Major sales spikes occurred approximately one week before major drops in in-stock rates, suggesting that demand surges (including panic buying) can act as early warning signals of supply stress. 
• Shifts in product type demand: Following the recall of certain powdered products, liquid concentrate and ready-to-feed formulas experienced sustained increases in demand, deviating from historical patterns. 
• Consumer experiences mirrored supply recovery: As in-stock rates improved and variability declined, households reported fewer difficulties obtaining formula, confirming alignment between supply metrics and lived consumer experiences. 
• Integrated monitoring improved situational awareness: Combining in-stock rates, sales data, and household surveys provided a more complete picture of supply dynamics than any single data source alone. 

Bigger Picture:

This study highlights the importance of supply-chain surveillance as a core component of food safety infrastructure, particularly for critical nutrition products such as infant formula. Unlike many foods, infant formula production is highly regulated and concentrated among relatively few manufacturers, making the system inherently vulnerable to disruption.

From a regulatory perspective, the study demonstrates the value of multi-source data integration, combining retail availability, national sales trends, and consumer experience surveys. Such integrated surveillance approaches could serve as models for monitoring other critical food systems, particularly those vulnerable to manufacturing interruptions or contamination-related recalls.

Overall, the 2022 shortage serves as a case study in food system resilience, emphasizing that maintaining supply continuity is not solely a manufacturing challenge but a systems-level public health responsibility involving production, regulation, distribution, and consumer behavior.

References:

1. Fenske et al. 2026. Dynamics of the U.S. 2022 Infant Formula Shortage and Recovery as Measured by In-Stock Rates, Sales, and Household Experiences. Journal of Food Protection.

Key Findings: 

This paper proposes adoption of the REP strain concept as a structured framework for long-term pathogen surveillance and investigation.¹

• Introduction of the REP framework: The authors propose categorizing certain pathogens as Reoccurring, Emerging, and Persisting (REP) based on long-term illness trends rather than single outbreak events, addressing a gap in traditional outbreak-focused surveillance models. 
• Evolution of subtyping technologies: The shift from serotyping and PFGE to WGS has dramatically improved the ability to link cases across time and geography, enabling identification of persistent strain clusters. 
• Long-term strain tracking across reservoirs: Case examples demonstrate that REP strains of pathogens such as Salmonella, Shiga toxin–producing E. coli, and Listeria move between humans, foods, animals, and environmental sources, maintaining transmission over extended periods. 
• Multiple epidemiologic patterns observed: The paper presents six case studies illustrating how REP strains exhibit distinct behaviors, including repeated seasonal outbreaks, steady endemic transmission, and gradual increases in incidence. 
• Need for cross-sector collaboration: Effective REP strain surveillance requires coordinated efforts across public health agencies, regulatory authorities, academia, and industry.
• Expanded surveillance beyond outbreak response: responding to acute illness REP investigations emphasize identifying root causes and environmental reservoirs, not just responding to acute illness clusters.

Bigger Picture:

The REP framework represents a significant conceptual shift in food safety and public health microbiology. Historically, surveillance systems were designed to detect discrete outbreaks, yet many pathogens do not follow this pattern. Instead, they persist in environmental niches or repeatedly re-enter the food system, causing illnesses that appear sporadic but are genetically linked. The integration of genomics-driven surveillance enables investigators to identify these hidden transmission networks and understand how pathogens adapt to survive in food processing environments, agricultural systems, and natural reservoirs. 

From a regulatory and industry perspective, the REP model highlights the importance of long-term environmental control and hazard monitoring, particularly for pathogens capable of forming biofilms or surviving under stress conditions. Rather than viewing contamination events as isolated failures, REP analysis encourages recognition of persistent ecological risks that require sustained mitigation strategies. Overall, the REP framework supports a transition from episodic outbreak management to continuous risk-based surveillance, strengthening the ability to prevent illnesses before they escalate into recognized outbreaks.

References:

1.  Chen et al. 2026. Reoccurring, Emerging, and Persisting (REP) Strains: A Framework for Surveillance and Investigation of Pathogens of Public Health Importance. Journal of Food Protection. 

Key Findings: 

Baldanzi et al. combined nationwide prescription records with fecal metagenomic sequencing data from 14,979 adults, allowing evaluation of antibiotic exposure over an 8-year period.¹

• Recent antibiotic exposure had the strongest effect: Antibiotic use within 1 year before sampling was associated with the largest reductions in microbial diversity, confirming strong short-term ecological disruption. 
• Long-term microbiome effects were detectable: Antibiotic use 1–4 years and 4–8 years prior to sampling remained significantly associated with reduced diversity and altered microbial composition, indicating long-lasting ecological effects. Even one antibiotic course administered 4–8 years earlier was associated with detectable microbiome changes, suggesting prolonged ecological consequences. 
• Certain antibiotic classes showed greater impact: Clindamycin, fluoroquinolones, and flucloxacillin accounted for the majority of observed associations with altered species abundance. Typically this was reduced species abundance, though greater abundance was observed for Enterocloster bolteae, E. citroniae (previously Clostridium bolteae and C. citroniae), Flavonifractor plautii, Ruminococcus gnavus and Eggerthella lenta – organisms linked with metabolic disease. 
• Certain antibiotic classes showed minimal impact: No associations were detected for extended-spectrum penicillins (that is, pivmecillinam and amoxicillin), amoxicillin-clavulanic acid or sulfamethoxazole-trimethoprim.
• Partial microbiome recovery occurred over time: Diversity recovery occurred most rapidly during the first two years after exposure, with slower recovery thereafter, indicating prolonged but incomplete restoration of microbial diversity. 
• Individual variation was observed: Differences in microbiome response varied by antibiotic class, sex, and age, indicating that host factors influence microbiome resilience and recovery dynamics.

Bigger Picture:

This study by Baldanzi et al. provides strong, population-level evidence that antibiotic exposure produces durable changes in the gut microbiome, reinforcing the concept that antimicrobial use has consequences beyond immediate therapeutic effects. Overall, these results highlight antibiotics as ecosystem-modifying agents, strengthening the rationale for minimizing unnecessary use and improving stewardship strategies aimed at preserving microbiome health.

References:

1. Baldanzi et al. 2026. Antibiotic Use and Gut Microbiome Composition Links From Individual-Level Prescription Data of 14,979 Individuals. Nature Medicine.

Key Findings: 

Deng et al. conducted a prospective study of 23 individuals with moderate to severe atopic dermatitis who received at least 2 courses of washed fecal microbiota transplantation (WFMT) derived from screened healthy donors.¹ This was a prospective before–and–after study. Clinical outcomes, peripheral blood, gut microbiome composition, and serum metabolomics were assessed before and after treatment.

• Clinical improvement: Participants exhibited statistically significant decreases in validated AD severity scores (e.g., EASI, SCORAD, NRS, DLQI) following treatment compared with baseline. Positive outcomes were more pronounced in adult vs pediatric subjects, which showed significant improvements in NRS (itch) scores alone.  
• Peripheral blood: absolute basophils counts were significantly reduced (P < 0.05), but other indicators were unchanged. 
• Altered gut microbiome composition: Recipients showed increases in microbial diversity and relative abundance of putative beneficial taxa (e.g., Bifidobacterium, Faecalibacterium) and decreases in pro-inflammatory taxa compared to baseline.
• Metabolomic shifts: Post-WFMT fecal samples from 17 subjects exhibited changes in microbiome-associated metabolites implicated in immune and barrier function, including short-chain fatty acids (SCFAs) and bile acid derivatives, aligning with improved clinical phenotype.
• Gut–skin axis correlation: associations between specific gut taxa/metabolites and AD severity were observed, supporting the mechanistic relevance of microbiota modulation.
• Altered skin microbiome composition: β-diversity analysis indicated remodeling of the AD skin microbiome, shifting towards less inflammatory skin populations.
• Safety and tolerability: WFMT was well tolerated; no serious adverse events related to transplantation were reported, underscoring feasibility for therapeutic application.

Bigger Picture:

This study adds to a growing body of evidence supporting the gut–skin axis as a therapeutic target in inflammatory skin diseases. By applying washed microbiota transplantation — a refined microbiome therapy with improved safety over traditional FMT — the authors demonstrate clinically meaningful improvement in atopic dermatitis severity accompanied by durable changes in gut microbial composition and metabolic output. These findings have broad implications for microbiome-based therapeutics, suggesting that targeted manipulation of gut ecosystems can modulate systemic immune responses and influence distal organ systems such as the skin. Future research will be needed to optimize donor selection, define responder phenotypes, and assess long-term efficacy and safety in larger, controlled trials.

References:

1. Deng et al. 2026. Washed Microbiota Transplantation Relieves Atopic Dermatitis via Gut–Skin Microbiome Rebalancing. BMC Microbiology.

Key Findings: 

Mafe et al. (2025) systematically reviewed current literature (35 records total) on postbiotics, addressing their sources, mechanisms, health benefits, formulation strategies, and regulatory considerations. ¹

• Definition and scope: Postbiotics encompass a broad range of non-viable microbial derivatives, including enzymes, organic acids, peptides, cell wall components, and other microbial metabolites that exert host benefits. 
• Mechanisms of action: Postbiotics modulate host systems through immunomodulation, metabolic regulation, gut-brain axis signaling, and anti-inflammatory effects, as evidenced by preclinical and clinical data. 
• Functional and formulation advantages: These compounds exhibit superior stability at ambient temperatures (e.g., ≥12 months at <25°C) and more predictable bioactivity than live probiotics, facilitating incorporation into functional foods. 
• Health outcomes: Evidence suggests postbiotics can support immune function, metabolic health, and potentially act against chronic disease pathways, though more definitive clinical trials are needed. 
• Innovation and regulation: Advances in formulation technologies, synthetic biology, and personalized nutrition, along with alignment to EFSA/FDA frameworks, create pathways for regulatory acceptance and commercialization.

Bigger Picture:

Postbiotics represent a maturing frontier in functional nutrition, bridging microbial ecology with food science and clinical health outcomes. Unlike probiotics, which require survival and colonization, postbiotics provide direct bioactive effects without viability constraints, making them attractive for products targeting immune, metabolic, and gut health — particularly where stability, safety, and consistent dosing are priorities. As mechanistic understanding deepens and regulatory definitions solidify, postbiotics are poised to expand functional food portfolios and support precision nutrition strategies that integrate microbiome-derived bioactives into mainstream dietary interventions.

References:

1. Mafe et al. (2025). Postbiotics in Functional Foods: Microbial Derivatives Shaping Health, Immunity and Next-Generation Nutrition. Food Frontiers.

Key Findings: 

Nguyen et al. (2026) developed and evaluated a novel Bacillus cereus Group Enrichment Broth and detection scheme designed to improve recovery of low-level B. cereus group organisms from 50 powdered infant formula (PIF) and infant cereal (IFC) samples. Whole-genome sequencing (WGS) and in vitro cytotoxicity assays were used to characterize the virulence of the isolates.¹

• High detection yield: The new enrichment and verification scheme recovered B. cereus group species in 52% of samples (26/50) that were initially found to be <100 CFU/g. 
• Dominant species recovered: 27 B. mosaicus and 12 B. cereus sensu stricto isolates. 
• Strong predictive performance: The enrichment approach had a predictive positive value (PPV) of 97.6% when confirmed by WGS; the single false-positive was identified as a Paenibacillus species.
• Genomic characterization: Sequencing provided deeper insights into the genetic diversity and potential virulence determinants of isolates recovered from infant foods.
  • 2 of 41 isolates carried the complete cereulide synthetase operon.
  • 36 of 41 isolates carried the complete nonhemolytic enterotoxin operon, which codes for a major diarrheal toxin.
  • 8 of 41 isolates carried the complete hemolysin BL operon, a major hemolytic diarrheal toxin.
  • 24 of 41 isolates carried the cytK-2 gene which codes for a high-virulence cytotoxin linked to severe, necrotizing illness.
• Detection does not equal hazard: In vitro cytotoxicity assays using Caco-2 cells demonstrated variable levels of toxicity among selected isolates, underscoring that not all B. cereus group members have equivalent virulence potential.

Bigger Picture:

On January 6, 2026, Nestlé announced a global recall of powdered infant formula due to potential presence of cereulide toxin produced by B. cereus – the first recall explicitly attributed to cereulide hazard rather than viable bacterial counts alone.

Nguyen et al.’s findings demonstrate that B. cereus group species frequently contaminate powdered infant formula and cereals. This poses significant risks since powdered infant formula is non-sterile and intended for vulnerable populations, while B. cereus spores survive standard thermal processing.

The primary public health concern stems from potential growth and toxin production during temperature abuse or extended holding after reconstitution. Even low initial contamination can create unacceptable health risks under these conditions.

These findings support implementing risk-based control measures including:

• Enhanced detection methods
• Strain-level characterization of isolates
• Surveillance programs based on hazard severity
• Refined microbiological criteria and process controls

For infant foods, this requires developing performance objectives and hygiene controls consistent with Codex Alimentarius principles to protect vulnerable populations and prevent future toxin-mediated events.

References:

1. Nguyen et al. 2026. Isolation and Characterization of Bacillus cereus Group Species in Powdered Infant Formula and Infant Cereal. Journal of Food Protection. 

Key Findings: 

Zhang et al. (2025) conducted a surveillance study of Salmonella in lymph nodes and tonsils collected from 560 cull hog carcasses at six U.S. processing facilities (three Western, three Eastern) across multiple seasons. Detection was performed using the BAX® System Real-Time Salmonella Assay, with enumeration via BAX-System-SalQuant.¹

• Overall prevalence: Salmonella was detected in 12.3% of individual lymph node and tonsil samples; 59.3% of carcasses (range: 53.9% in winter to 64.2% in summer/fall) were positive in at least one lymphatic tissue.
• Highest-risk tissues: Tonsils exhibited the highest prevalence (36.9%), followed by mesenteric lymph nodes (29.7%); other lymph nodes (e.g., subiliac, tracheobronchial, prescapular, axillary) showed prevalences below 10%.
• Seasonal patterns: Tonsil prevalence peaked in summer/fall (42.6%), while mesenteric lymph nodes showed higher prevalence in spring and summer/fall compared with winter.
• Regional and tissue-specific variation: Certain lymph node types (e.g., superficial inguinal) demonstrated higher winter prevalence in Eastern facilities.
• Quantitative burden: Enumerable mesenteric lymph nodes contained significantly higher Salmonella concentrations in winter, particularly in Eastern regions.

Bigger Picture:

This study demonstrates that internal lymphatic tissues—especially tonsils and mesenteric lymph nodes—are important reservoirs of Salmonella in cull hogs entering the processing chain. Because these tissues are not mitigated by surface decontamination and may be incorporated into comminuted products, they represent a meaningful food safety risk. The prevalence and concentration data provided establish a baseline to inform quantitative microbial risk assessments, targeted processor interventions (e.g., lymph node removal or focused controls), and future regulatory considerations.

References:

1. Zhang et al. 2025. Surveillance of Salmonella in Cull Boar, Sow, and Gilt Lymph Nodes and Tonsils from Six Cull Hog Processing Facilities in the United States. Journal of Food Protection.