Reinforced cassava starch based edible film with essential oil and clay nanoparticles | |
| Author | Butsadee Iamareerat |
| Call Number | AIT Thesis no.FB-10-10 |
| Subject(s) | Cassava Starch Edible coatings |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Engineering and Bioprocess Technology, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. no.FB-10-10 |
| Abstract | At present, the demands for biodegradable packaging from renewable source are intensive . Therefore, the development of biodegradable packaging based on biopolymers has attracted attention. Starch is a biopolymer that is an attractive alternative for packaging material because it is a cheap material due to its abundance and availability. In addition, the active substances such as essential oils of plants and clay are incorporated into the packaging in order to improve the physical and mechanical properties including antibacterial property. The main objective of essential oils which are incorporated into the biodegradable or edible film is to enhance the efficacy of film for inhibiting the growth of microorganism which may contaminate in food. Moreover, clay; such as sodiumbentonite, is applied to the film in order to impro ve the oxygen permeability and water vapor permeability of film. This study was carried out to utilize the beneficial potency of essential oils (cinnamon oil and oregano oil) and clay of sodiumbentonite to develop the physical, mechanical and antimicro bial properties of films. Initially, cinnamon oil and oregano oil were tested for antimicrobial activities against Escherichia coli , Salmonella typhimurium and Staphylococcus aureus by determining the MICs value. After that, both essential oils at differen t concentrations were incorporated into the cassava starch films and the physical, mechanical and antimicrobial properties of films were then tested. The essential oil that was suitable for incorporating into the cassava starch films was selected for furth er study. Subsequently, the effect of glycerine and sodiumbentonite to the properties of films were studied by using the experimental design of factorial in CRD and the best film was selected. Finally, both selected essential oil at different concentration s and the suitable concentration of glycerine and sodiumbentonite were incorporated into the cassava starch film. The physical, mechanical and antimicrobial properties of films were then tested. The best film was selected in order to apply to pork meatball s for prolonging the shelf life. When tested against the above mentioned bacteria, it was found that both cinnamon oil and oregano oil could inhibit the growth of tested microorganisms. The cinnamon oil was more suitable than oregano oil for incorporatin g into the cassava starch films. The water vapor permeability and the tensile strength of cassava starch films incorporated both essential oil decreased when the concentration of essential oils increased. The elongation at break (%) of cassava starch films incorporated essential oils increased when the concentration of essential oils increased. The cassava starch films incorporated with 0.1% oregano oil or lower could not inhibit the growth of tested microorganisms but the cassava starch films incorporated with cinnamon oil not less than 1.5% could inhibit the growth of tested microorganisms. Therefore, the cinnamon oil was more suitable than oregano oil for incorporating into the cassava starch films. The addition of sodiumbentonite decreased the water va por permeability of composite films but the water vapor permeability tended to increase when the concentration of glycerine increased except at 0.25% sodiumbentonite. The tensile strength increased when the concentration of sodiumbentonite increased and th e elongation at break (%) of composite films decreased when the concentration of sodiumbentonite increased. The tensile strength decreased when the concentration of glycerine increased and the elongation at break (%) of composite films increased when the c oncentration of glycerine increased. There were no antibacterial properties in case of cassava starch composite films. From the result, the best composite film was composed of 0.75% sodiumbentonite and 2% glycerine The water vapor permeability and oxygen permeability of composite films increased as the concentration of cinnamon oil increased. The tensile strength and elongation at break (%) decrease when the concentration of cinnamon oil incorporated into the composite films increased. The composite films exhibit the antibacterial properties as the cinnamon oil was incorporated and the composite film incorporated with 2.5% cinnamon oil was the best film. Moreover, the surface microstructures of all types of cassava starch films were studied by using Scan ning Electron Microscope (SEM) . The interactions of active substances were studied by using Fourier Transform Infrared (FTIR) . For the application, the pork meatballs contained in packaging based on cassava starch incorporated 0.75% sodiumbentonite and 2 .50% cinnamon oil packaging reached maximum allowable level when the pork meatballs were stored for two days whereas the pork meatballs contained in plastic bag and packaging based on cassava starch reached maximum allowable level within one day. There was no difference of the shelf life of pork meatballs which were contained in different types of packaging at refrigeration temperature. The hardness and chewiness of pork meatballs which were contained in the composite packaging incorporated cinnamon oil wer e different from other packages whereas the cohesiveness and springiness of pork meatballs which were stored in room temperature and refrigeration temperature were similar. |
| Year | 2010 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. no.FB-10-10 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Anal, Anil Kumar; |
| Examination Committee(s) | Athapol Noomhorm;Rakshit, Sudip Kumar; |
| Scholarship Donor(s) | RTG Fellowships; |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2010 |