Gelatin films with nisin and catechin for minced pork preservation

The capacity of gelatin-based active films to extend the shelf-life of minced pork meat was investigated. In vitro antibacterial and antioxidant activity of films resulted from nisin and catechin incorporation, respectively. Cross-linking of gelatin macromolecules by microbial transglutaminase (MTGase) added in film-forming suspensions resulted in a marked decrease of the films solubility in water. Gelatin films reticulated by MTGase with or without (control) nisin and catechin were thus used to overwrap minced pork meat stored in trays at 5 degrees C for 7 days. Their gas barrier properties were high enough for the self-development by the respiratory activity of meat microflora of a modified atmosphere with a decreased oxygen and an increased carbon dioxide concentration over 7 days. Interestingly, gelatin films with nisin and catechin retarded lipid oxidation and microbial growth: the time to reach a total viable count of 107 CFU. g(-1) of meat was extended from 1 to 4 days.