Production of Cellulosic Bioactive and Antimicrobial film modified by Chitosan
Dr. Ilham Ismael Tami Al-Shemari/College of agriculture
Antimicrobial membranes were prepared using date syrup as medium with the modification of chitosan which was applied by various methods. The result showed that cellulose membranes soaked with chitosan of concentrations 0.1 , 0.5, 1, 1.5, %2 for 48h and powdered cellulose-chitosan membranes showed higher inhibition against pathogenic bacteria which includes Klebsiellapneumoniae, E.coli, Staph. aureus, Salmonella typhimurium, Serratiamarcescens, Pseu. aeruginosa, were with the application of cellulose membranes soaked in 2% chitosan. The diameter of inhibition zone was obtained against Klebsiella pneumonia bacteria and E.coli. The highest diameter of the transparent zone were 18.23, 16 mm . On the other hand, the diameter of Staph. aureus, Salmonella typhimurium, Serratiamarcescens, Pseu. aeruginosa bacteria were 14.31, 12.8, 12.47, 12 mm respectively. Application of cellulose powder- chitosan in the ratio of 5:2, resulted in the highest inhibition against Klebsiellapneumoniae, E.coli, Staph. aureus bacteria which had diameter of 22.3, 21.2, 19.1 respectively. Some characteristics of membranes which showed high inhibition against pathogenic bacteria were studied: cellulose membranes soaked in 2%chitosan, These membranes thickness,swellings,permeability, water permeability, strength power and IR were 0.78 mm, 48.63%, 13.7%, 1.25, 101.1MPa respectively. Infra red spectroscopy showed interference possibility of chitosan of within the cellulose membrane composition. Cellulose membranes produced by Acetobacterxylinum soaked in 2% chitosan for 48hr were used in extending the shelf life of minced beefstored for 14 day in refrigerator at 4 C. Microbiological test for cellulose- chitosan membranes showed reduction of total bacterial counts, coliform, psychrophilic, and staphylococcus aureus were reduced from 5.65, 4.56, , 4.17, , 2.09at zero time to 5.23, 4.38, 4.07 , 3.01 after 14 days of refrigeration storage at 4 C as compared with control treatment which resulted in increases in these accounts after the same period and conditions of storage to9.92, 9.43, 6.91, 6.01 respectively.Chemical tests showed obvious variation in the peroxide values POV and TBA values of minced meat coated by cellulose- chitosan from5.68, 2.84 at zero storage time to 10.12,5.63 at the end of storage period as compared with control treatment which were coated by cellulose untreated by chitosan. The PO and TBA values were increased at the end of the storage period to 23.23 and 11.21. There was no clear change in pH values of minced meat and chicken burger during the period of storage. Moisture content were decreased during storage for all of samples coated by cellulose- chitosan and control samples. These changes were varied however, it was decreased in minced meat and chicken burger coated by cellulose- chitosan from 65.78to 63.45as compared with control treatment in which it was decreased from 65.78 to 60.26respectively. No variations were observed in fat and ash content of samples coated with cellulose- chitosan and control samples.