title: Compositional and physicochemical factors governing the viability ofLactobacillus rhamnosusGG embedded in starch-protein based edible films.
abstract: Probiotic incorporation in edible films and coatings has been shown recently to be an efficient strategy for the delivery of probiotics in foods. In the present work, the impact of the compositional, physicochemical and structural properties of binary starch-protein edible films onLactobacillus rhamnosusGG viability and stability was evaluated. Native rice and corn starch, as well as bovine skin gelatine, sodium caseinate and soy protein concentrate were used for the fabrication of the probiotic edible films. Starch and protein type both impacted the structural, mechanical, optical and thermal properties of the films, and the process loss ofL. rhamnosusGG during evaporation-dehydration was significantly lower in the presence of proteins (0.91-1.07 log CFU/g) compared to solely starch based systems (1.71 log CFU/g). A synergistic action between rice starch and proteins was detected when monitoring the viability ofL. rhamnosusGG over four weeks at fridge and room temperature conditions. In particular, a 3- to 7-fold increase in the viability ofL. rhamnosusGG was observed in the presence of proteins, with sodium caseinate - rice starch based films offering the most enhanced stability. The film's shelf-life (as calculated using the FAO/WHO (2011) basis of 6 log viable CFU/g) ranged between 27-96 and 15-24 days for systems stored at fridge or room temperature conditions respectively.
authors.affiliation: Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology (LIST), 41 Rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Christos
authors.initials: C
authors.lastname: Soukoulis
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, Leicestershire, United Kingdom.
authors.forename: Poonam
authors.initials: P
authors.lastname: Singh
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, Leicestershire, United Kingdom.
authors.forename: William
authors.initials: W
authors.lastname: Macnaughtan
authors.affiliation: Nottingham Nanotechnology and Nanoscience Centre, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Christopher
authors.initials: C
authors.lastname: Parmenter
authors.affiliation: Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, Leicestershire, United Kingdom.
authors.forename: Ian D
authors.initials: ID
authors.lastname: Fisk
keywords: Corn starch; Gelatine; Probiotics; Rice starch; Sodium caseinate; Soy protein