Development of Chitosan Blended Adlay Starch Films for Antimicrobial Packaging to Extend Shelf Life of Fruits

Abstract

The objective of this research was to study the forming of adlay starch film. The glycerol concentrations of 10, 15and20%(w/w, starch basis) were tested to determine an optimal one to be used as plasticizer. The glycerol was added into the dispersions at Physical properties including thickness, tensile strength, elongation value and biodegradation were evaluated. The results indicated that adlay starch with 10% glycerol showed the maximum tensile strength of 0.34??0.03 MPa while the elongation value of this condition was the lowest at 36.52??1.05 mm. When glycerol concentration was raised to over 20%w/w, it presented the lowest tensile strength (0.08??0.01MPa) with an elongation that reached 53.07??5.92 mm. The adlay starch film with 20% glycerol was completely degraded within the shortest time period of 14 days.For the antimicrobial activity of films mixed with different chitosan concentrations, the greatest antimicrobial activity against three bacteria tested was the effect of starch films containing 1.5 and 2.0% of chitosan. Moreover, the results indicated that bananas packed into starch films with 1.5% and 2.0%w/w chitosan demonstrated their shelf life extension until to 14 days.