title: The effect of bacteriophages on the acidification of a vegetable juice medium by microencapsulated Lactobacillus plantarum.
abstract: Starter cultures are increasingly being used for the production of sauerkraut, kimchi and other fermented vegetables. The goal of this study was to determine whether the microencapsulation of a bacterial culture can prevent phage infection during vegetable fermentation. Lactobacillus plantarum HER1325 was microencapsulated in alginate beads. Some beads were used without further processing, while others were freeze-dried prior to testing. Fresh beads (diameter of 2 mm) and dried cultures of the lactobacilli (particle size of 53-1000 μm) were added to a vegetable juice medium (VJM) at 1 × 107CFU/mL. The virulent phage HER325 was added at an initial titer of 1 × 104PFU/mL. In the absence of phages, the pH of the vegetable juice dropped to 4.2 after 40 h of fermentation at 19 °C. In the presence of phage HER325, acidification by both the non-microencapsulated and microencapsulated starter cultures stopped after 24 h. In all assays, the alginate particles dissolved during the 40 h of VJM fermentation. When 15 g/L of calcium chloride was added to the VJM, the alginate beads did not dissolve and significant phage protection was observed. The results suggest that phage-protected microencapsulated starter cultures can be used for vegetable fermentation if means are taken to prevent them from dissolving during acidification.
authors.affiliation: Saint-Hyacinthe Research and Development Centre, Agriculture and Agri-Food Canada, 3600, Casavant Blvd W., Saint-Hyacinthe, Quebec, J2S 8E3, Canada; Institute of Nutrition and Functional Foods (INAF), Université Laval, 2440, Hochelaga Blvd., Quebec City, Quebec, G1V 0A6, Canada. Electronic address: claude.champagne@agr.gc.ca.
authors.forename: Claude P
authors.initials: CP
authors.lastname: Champagne
authors.affiliation: Département de Biochimie, Microbiologie et bio-informatique, Faculté des Sciences et génie, Université Laval, 1045, Avenue de la Médecine, Quebec City, Quebec, G1V 0A6, Canada; Félix d'Hérelle Reference Center for Bacterial Viruses, Faculté de Médecine Dentaire, Université Laval, 2420, Rue de la Terrasse, Quebec City, Quebec, G1V 0A6, Canada.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Moineau
authors.affiliation: Saint-Hyacinthe Research and Development Centre, Agriculture and Agri-Food Canada, 3600, Casavant Blvd W., Saint-Hyacinthe, Quebec, J2S 8E3, Canada.
authors.forename: Sonia
authors.initials: S
authors.lastname: Lafleur
authors.affiliation: Saint-Hyacinthe Research and Development Centre, Agriculture and Agri-Food Canada, 3600, Casavant Blvd W., Saint-Hyacinthe, Quebec, J2S 8E3, Canada.
authors.forename: Tony
authors.initials: T
authors.lastname: Savard
mesh_terms: D000464:Alginates; D001435:Bacteriophages / Q000502:physiology*; D001672:Biocompatible Materials / Q000737:chemistry; D002122:Calcium Chloride / Q000494:pharmacology; D015169:Colony Count, Microbial; D004339:Drug Compounding; D005285:Fermentation; D005516:Food Microbiology / Q000379:methods; D000067030:Fruit and Vegetable Juices / Q000032:analysis* / Q000382:microbiology / Q000821:virology*; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006863:Hydrogen-Ion Concentration; D048191:Lactiplantibacillus plantarum / Q000737:chemistry / Q000502:physiology*
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D002122:Calcium Chloride
keywords: Alginate; Bacteriophage; Fermented vegetables; Lactic acid bacteria; Microencapsulation