Optimization and Application of Chitosan as Natural Product from Locally Available Shrimp Shell in Bangladesh

The experiment was designed to investigate the optimization condition of chitosan and its application on fruit as natural preservative prepared from locally available shrimp shell in Bangladesh. Materials and methods. The preparation of chitosan was done by gravimetric method; characterization of chitosan was performed by solubility. pH, viscosity, FT-IR, SEM, XRD and DDA test. The prepared chitosan (0.5-0.25%) was completely soluble in 1% and 2% acetic acid solution. Based on these spectra, the major absorption band was observed at 3485.14 cm-1 which indicated the stretching vibration of OH and NH groups. 1045.42 cm-1 which represented the free amino group (-NH2) at C2 position of glucosamine indicated an important group that might present in chitosan The SEM micrographs were implicated non-homogenous and non-smooth surface on chitosan. The XRD pattern of the chitosan sample was illustrated one sharp and strong characteristic broad diffraction peak at 2θ = 20°. Degree of deacetylation (DDA) of the prepared chitosan was 84.0%. Application of chitosan solution (0.25%) on red and green apple was observed that control was started to form wrinkle at 5th day while test sample had no colour change at 18th day for red apple. It was also found that green apple had to change color at 7th day & to form wrinkle at 15th day for control while test sample had no color change at 15th day for a test sample. Therefore it can be concluded that the application of chitosan solution on red and green apple at a concentration of 0.25% solution could be a natural preservative for fruit (apple) preservation.