Abstract:
The objective of this research was to use chitosan coating for shelf life extension of refridgerated ready-to-eat food product. The research was separated into 3 sections. Firstly, the optimum packaging material and condtion for packaging of brioled boneless por1<. (BBP) was determined by using polypropylene bag under atmospheric air (OPP) and polyamide bag under atmospheric air (PA) and vacuum condition (PA-V) and stored at 2 ± 1 °C. The results suggested that PA-V could maintain qualities including color, texture, pH, peroxide values (POV) and organoleptic qualities of BBP better than PA and OPP. Therefore, PA-V was used for further experiment. Secondly, the optimum method for preparation of chitosan coating was determined by using different solvents including lactic acid 1% (wlv) and acetic acid 1% (w/v) and different concentrations of plasticizer including 0, 10, 20 and 30 % w/w of chitosan. It was found that using acetic acid, the chitosan film had higher tensile strength (TS), while thickness, elongation at break (% EAS) and water 'vapor transmission rate (WVTR) were not different from those using lactic acid. It was also found that 20 % plasticizer was optimum to be used for preparing chitosan film because the film had higher % EAB, while maintaining thickness, TS, and WVTR. Lastly, the effect of using chitosan coating on qualities and shelf life of BBP was determined by coating the BBP with chitosan concentrations of 2.0 % w/v (Coat-A) and 2.5 % w/v (Coat-B), SSP without chitosan coating was used as Control. All samples were then packaged in PA-V and stored at 2 ± 1°C. It was found that BBP coated with chitosan could maintain color, texture, pH, POV and organoleptic qualities better than Control. The results suggested that chitosan coating could inhibit microbial growth and lipid oxidation of the product and thus extending the shelf life of the SSP, Control samples had had shelf life of less than 21 days, while BBP coated with chitosan had shelf life of up to 28 days .
