Biopreservation of Chocolate Mousse with <i>Lactobacillus</i> <i>helveticus</i> 2/20: Microbial Challenge Test
Bogdan Goranov,
Desislava Teneva,
Rositsa Denkova-Kostova,
Vesela Shopska,
Nadia Oulahal,
Zapryana Denkova,
Georgi Kostov,
Pascal Degraeve,
Rafael Pagan
Affiliations
Bogdan Goranov
Department “Microbiology”, University of Food Technologies—Plovdiv, 26 Maritza Boulevard, 4002 Plovdiv, Bulgaria
Desislava Teneva
Laboratory of Biologically Active Substances, Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 139 Ruski Boulevard, 4000 Plovdiv, Bulgaria
Rositsa Denkova-Kostova
Department “Technology Biochemistry and Molecular Biology”, University of Food Technologies—Plovdiv, 26 Maritza Boulevard, 4002 Plovdiv, Bulgaria
Vesela Shopska
Department “Technology of Wine and Beer”, University of Food Technologies—Plovdiv, 26 Maritza Boulevard, 4002 Plovdiv, Bulgaria
Nadia Oulahal
Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires Research Unit, IUT Lyon 1, Technopole Alimentec, Université Claude Bernard Lyon 1, ISARA Lyon, 155 rue Henri de Boissieu, F-01000 Bourg en Bresse, France
Zapryana Denkova
Department “Microbiology”, University of Food Technologies—Plovdiv, 26 Maritza Boulevard, 4002 Plovdiv, Bulgaria
Georgi Kostov
Department “Technology of Wine and Beer”, University of Food Technologies—Plovdiv, 26 Maritza Boulevard, 4002 Plovdiv, Bulgaria
Pascal Degraeve
Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires Research Unit, IUT Lyon 1, Technopole Alimentec, Université Claude Bernard Lyon 1, ISARA Lyon, 155 rue Henri de Boissieu, F-01000 Bourg en Bresse, France
Rafael Pagan
Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Instituto Agroalimentario de Aragón-IA2, Universidad de Zaragoza-CITA, Calle Miguel Servet, 177, 50013 Zaragoza, Spain
Probiotic bacteria are used for food biopreservation because their metabolic products might contribute to ensuring food microbiological safety and/or increase its shelf life without the addition of chemical preservatives. Moreover, biopreserved foods are excellent vehicles for the delivery of probiotic bacteria. The aim of the study was to investigate the potential of chocolate mousse food matrix for the delivery of the probiotic strain Lactobacillus helveticus 2/20 (Lb. helveticus 2/20) and to investigate its capacity to inhibit the growth of two foodborne pathogenic bacteria (Staphylococcus aureus and Escherichia coli). Therefore, the populations of free or encapsulated in calcium alginate Lb. helveticus 2/20 cells and/or of each pathogen (used to voluntarily contaminate each sample) were monitored both in complex nutrient medium (MRS broth) and in chocolate mousse under refrigeration conditions and at room temperature. Lb. helveticus 2/20 alone in free or encapsulated state effectively inhibited the growth of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923 in chocolate mousse when stored at 20 ± 2 °C. Practically no viable unwanted bacteria were identified on the 7th day from the beginning of the process. High viable Lb. helveticus 2/20 cell populations were maintained during storage under refrigerated conditions (4 ± 2 °C) and at room temperature. Chocolate mousse is thus a promising food matrix to deliver probiotic Lb. helveticus 2/20 cells, which could also protect it from contamination by unwanted bacteria.
