Work

Occurrence, persistence and pathogenic potential of Bacillus cereus sensu lato strains isolated during processing of two plant-based desserts

Year: 2026

Type: article

Abstract: Ensuring the microbiological safety of plant-based foods is challenging, particularly during the development of new products. This study aimed to map and identify Bacillus cereus during the production of two plant-based desserts: one fermented and one non-fermented, in order to identify critical processing stages. A bacterial survey was conducted along the processing line of each dessert and 120 samples were collected from raw materials, processing stages, and during product storage. Total bacterial counts ranged from <1.0 to 10.1 ± 0.0 Log10 CFU/g during processing while mesophilic spore counts varied between <1.0 to 2.5 ± 0.7 Log10 CFU/g. Thermophilic and B. cereus spores remained below the detection limit (1.0 Log10 CFU/g). A selective enrichment demonstrated that B. cereus was present during all steps of both processes. In total, 127 B. cereus Group isolates were recovered from ingredients, processing steps and conditioned products. Analysis assigned these isolates to phylogenetic groups II, III, IV and VII, with group IV strains being the most prevalent. Several strains persisted throughout processing, indicating their resilience to technological treatments. Approximately 60% of the isolates carried the enterotoxin gene combination hbl–nhe–cytK, whereas the emetic ces gene was detected only once. B. cereus growth was observed in the non-fermented dessert when storage temperatures reached 10°C, but no growth was detected in the fermented product. These findings provide crucial insights into contamination pathways and the persistence of B. cereus during processing, which will help to design safe processing conditions for plant-based dairy alternatives.

Source: Food Microbiology

DOI: 10.1016/j.fm.2026.105303

Authors: Marine Zanetti, Marie-Hélène Guinebretière, Stéphanie Oriol, Fanny Canon, Isabelle Souchon, Véronique Broussolle

Institutions: Université d'Avignon et des Pays de Vaucluse, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Sécurité et Qualité des Produits d'Origine Végétale

Language: English

Topic: Bacillus and Francisella bacterial research

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDGs: Zero hunger, Good health and well-being

Open Access status: hybrid

Estimated APC paid: $4,210