Test of tensile strength (TS) of chitosan films
ASTM D882 standards for testing TS (ASTM,1997) were used. The 10x150 mm2 of film pieces were stored under the temperature of 23oC with 50% relative humidity for at least 40 hours. To test the tensile strength, both ends of the samples were secured with the texture analyzer (model TA.XT plus, Stable Micro Systems Ltd., UK). The testing speed was at 50 m/min with a load cell of 0.5 KN. The distance between the two anchorages was 100 mm. The following formula was used in calculating the tensile strength and elongation.