Abstract: Cinnamaldehyde-chitosan (CIN-CS) composite films with different initial concentrations (0.5%, 1.0%, 1.5% and 2.0% (V/V)) of CIN were prepared. The thermal stability of these films was increased by increasing concentration of cinnamaldehyde. The release of cinnamaldehyde from these films into headspace and fatty food stimulants such as isooctane at 4, 25 and 40 ℃ was studied using gas chromatography-mass spectrometry. The efficacy of 2.0% CIN-CS film versus blank control and pure CS film in preserving the quality of fresh pork during storage at 4 ℃ was evaluated with respect to pH, total bacterial count, total volatile basic nitrogen (TVB-N) and sensory evaluation. Our results indicated that CIN addition improved the thermal stability of the CS films. The release of CIN from 2.0% CIN-CS increased with time and temperature, reaching 59.22% when equilibrium was attained at 40 ℃. The release rate of CIN into isooctane decreased with increasing CIN concentration, whereas it increased with increasing temperature. When applied on fresh pork, the 2.0% CIN-CS film showed a significant decrease in pH, TVB-N and total bacterial count as well as better sensory evaluation compared with the pure CS film and the blank control (P < 0.05). The shelf life of 2.0% CIN-CS film packaged pork was 7 d, while that of the blank group was 4 d.

Key words: chitosan film, cinnamaldehyde, release, active packaging, preservation of fresh pork