Shelf life extension of fish fillet and tomato using edible antimicrobials | |
| Author | Supanoi Suntipiriyaporn |
| Call Number | AIT Thesis no. BT-03-18 |
| Subject(s) | Chitosan Fish fillets Anti-infective agents |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. BT-03-18 |
| Abstract | In the study the fish fillets are used in order to see the possible preservative effect by use two-preservation solutions chitosan and a commercial product. Microbiological, chemical, and sensory evaluation was done for these products. Post harvest treatment of tomatoes was using chitosan to study shelf life extension. Indeedly the antimicrobial activity of chitosan and mionix solution on food pathogenic bacteria (Escherichai coli, Salmonella, Vibrio cholerae, Staphylococcus aureus, and Listeria monocytogenes) were tested in vitro. The results showed that at 0.1 %, 0.5%, and 1 % chitosan can inhibit the growth of five organisms, 0.5% and 1 % chitosan were showed the most sensitivity with all organisms especially with E. coli and S. aureus. V. cholerae and L. monocytogenes were showed the most sensitivity with all mionix solutions except E. coli was the less sensitivity with mionix solutions. The antimicrobial activities of chitosan and mionix solution to inhibit food pathogenic bacteria in sterilized fish fillets were then studied. The fish fillets were dipped in difference concentrations of chitosan and mionix solution. Then these samples were dipped in food pathogenic bacteria, and then incubated at 37 ° C for 60 hours. The results shown that chitosan and mionix solution extend the lag phase of all organisms and Listeria monocytogenes was the most sensitivity to chitosan and mionix solution than the other organisms. The activities of chitosan and mionix solution on preservation of non- sterilized fish fillets were then studied. These samples were dipped in the concentrations of chitosan and mionix solution were used as previously study and stored in refrigerator at 4 °C to study the extension shelf life up to 30 days. The total plate count, total volatile base nitrogen (TVB-N), trimethylamine (TMA), and sensory evaluation are involved in this study. The results shown that the roles of chitosan and mionix solution were significant for preservation. They extended shelf life of fish fillets to 15-20 days, which the control sample was only 10 days. The preservation of chitosan on tomatoes. For post harvest preservation tomatoes were dipped in the 0.1 % and 1 % chitosan and then storage at 25 °C for 30 days. The storage parameters tested were weight loss, color change, and firmness to study the shelf life of tomatoes. The results does not show significant different in the concentration 0.1 % and 1 % chitosan for all storage parameters. The mechanism of chitosan and a commercial product of mionix on cell wall of Escherichiia coli were investigated by scanning electron microscope(SEM). E. coli was grown on nutrient broth medium contained above solutions. SEM of E. coli revealed severe damage of cells resulted in irregular shapes, swelling of cell wall and dissociation of outer membrane. |
| Year | 2003 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. BT-03-18 |
| 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) | Sudip K. Rakshit; |
| Examination Committee(s) | Vinod K. Jindal;Athapol Noomhorm; |
| Scholarship Donor(s) | Asian Institute of Technology; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2003 |