No abstract

Edible Gelidium corneum-gelatin (GCG) blend films containing grapefruit seed extract (GFSE) or green tea extract (GTE) were manufactured, and the quality of pork loins packed with the film during storage was determined. Tensile strength (TS) and water vapor permeability (WVP) of the films containing GFSE or GTE were better than those of the control. The film's antimicrobial activity against Escherichia coli O157:H7 and Listeria monocytogenes increased with increasing antimicrobial concentration, resulting in a decrease in the populations of bacteria by 0.77 to 2.08 and 0.91 to 3.30 log CFU/g, respectively. Pork loin samples were inoculated with E. coli O157:H7 and L. monocytogenes. The samples packed with the GCG film containing GFSE (0.08%) or GTE (2.80%) had a decrease in the populations of E. coli O157:H7 and L. monocytogenes of 0.69 to 1.11 and 1.05 to 1.14 log CFU/g, respectively, compared to the control after 4 d of storage. The results showed that the quality of pork loins during storage could be improved by packaging them with the GCG film containing GFSE or GTE.

Edible RP films prepared in the present investigation can be applied in food packaging.

We prepared an edible film of Gelidium corneum (GC) containing carvacrol as an antimicrobial and antioxidative agent. The GC film containing carvacrol significantly decreased the WVP, while TS and %E values were increased, compared to the film without carvacrol. Increasing amounts of an antimicrobial agent increased antimicrobial activity against Escherichia coli O157:H7 and Listeria monocytogenes. Application of the film to ham packaging successfully inhibited the microbial growth and lipid oxidation of ham during storage. Our results indicate that GC film can be a useful edible packaging material for food products, and the incorporation of carvacrol in the GC film may extend the shelf life.

In this study, we aimed to improve the physical properties of Gelidium corneum-gelatin (GCG) film by including nano-clay in the film-forming solution and tested the antimicrobial properties of the thymolcontaining composite film as a packaging material for chicken breast. Addition of nano-clay improved the physical properties of GCG film. The tensile strength of the GCG film containing 1% Cloisite Na + was 38.13 MPa, compared to the 26.65 MPa for the GCG film. The water vapour permeability of the GCG film was 3.56 ng m m )2 sPa, while that of the GCG film with 1% Cloisite Na + was 3.24 ng m m )2 sPa. Incorporation of thymol into the film had its antimicrobial activities against Escherichia coli O157:H7 and Listeria monocytogenes. When used to pack chicken breast, the GCG ⁄ nano-clay film containing thymol inhibited microbial growth during storage.