CONICET | Buscador de Institutos y Recursos Humanos

Bacteriocins as food preservatives in packaging systems have received increased interest in recent years. In the active packaging field, renewable resources based films from corn, soy, wheat proteins and starch have been widely studied and different strategies of film manufacture were developed. A polymeric material in contact with food experiments a mass transfer process which involves diffusion and dissolution of some components from the packaging to the food, this probably causing packaging activity loss. In this work, a spread-coating wheat gluten film activated with Lactobacillus curvatus CRL705 bacteriocins was periodically assayed for antimicrobial stability against the indicator strains during tree month of storage at 23°C and a study of specific migration into aqueous simulant was performed. Prior to testing, all film specimens were conditioned for two days in an environmental chamber at 50% relative humidity and 23 ºC. During storage, antimicrobial activity showed to be stable for lactocin 705 while a slight decrease for lactocin AL705 was observed. Although specific migration studies revealed antimicrobial activity into the aqueous simulant for both bacteriocins, water contacted films remained active against the indicator strains. On the other hand, reduction of bacteriocins specific migration was observed during the storage period. Results suggest that wheat gluten structure might be changing by aging during storage and a certain degree of crosslinking may occur, this being favorable to bacteriocins mass transfer decrease. This research presents an evidence of the effectiveness of a wheat gluten film activated with L. curvatus CRL705 bacteriocins during a tree months period.