Incorporation of spray dried and freeze dried blackberry particles in edible films: Morphology, stability to pH, sterilization and biodegradation

Blackberry pulp powder (B, without encapsulating agent) and microencapsulated blackberry pulp (M, with encapsulating agent) obtained by freeze drying (L) and spray drying (S) were incorporated in the arrowroot starch film-forming solution directly (D) and by sprinkling (S), in concentrations of 0, 20, 30 and 40% (blackberry solids mass/biopolymer mass), to produce active food packaging. The blackberry powders presented antioxidant capacity. SEM images showed that incorporation of blackberry powder in the film-forming solution caused heterogeneity in the starch matrix and made its surface rough and irregular. Films incorporated with sprinkling blackberry powder had higher antioxidant capacity and were more soluble in acidic, neutral and alkaline solutions in relation to films directly incorporated, showing great potential to be used as vehicle for releasing of antioxidant compounds into the surroundings. There was darkening of films with blackberry pulp after sterilization process. Films showed almost entirely disintegration after 38-days of composting.