Soy protein isolate-essential oils based edible film for food packaging | |
| Author | Supusanee Dulyakasem |
| Call Number | AIT Thesis no.FB-10-13 |
| Subject(s) | Soy proteins Edible coatings Food--Packaging |
| Note | A thesis submitted in partial fulfillment of requirements for the degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. no.FB-10-13 |
| Abstract | The efficacy of essential oil of cinnamon leaf (Cinnamomum zeylanicum) and oregano (Origanum vulgare) as natural antimicrobial agents was investigated using agar well diffusion assay. Three foodborne pathogens, namely, Escherichia coli 0157:H7, Salmonella typhimurium and Staphylococcus aureus were selected as the target microorganisms to evaluate their sensitivity to both essential oils. The minimum concentrations that can be inhibited the microbial growth around the well of cinnamon leaf oil and oregano oil were 0.33% (v/v) for Escherichia coli 0157:H7 and 0.75% v/v) for Salmonella typhimurium and Staphylococcus aureus. In the second part of the study, 5% (w/v) soy protein isolate and various concentrations of glycerol (50, 60 and 70% v/v) were dissolved in water and casted to obtain dried edible films. Films with antimicrobial property were formulated by adding two concentrations (0.5 and 1.0%v/v) of cinnamon leaf oil and oregano oil. Antimicrobial activities against the aforementioned foodborne pathogens expressed that all the film specimens with essential oils showed the inhibition of growth at the film contact surface. A study of physical, mechanical and barrier properties of the resulting films showed that the overall color of soy protein films increased in yellow color upon the addition of additives. The tensile strength (TS) and the percent elongation at break (EB) varied independently with the concentration of the additives. Both essential oils lower the WVP of the films in the range of 0.01 to 0.05 g.mm/m2.kPa.day, while glycerol increased the WVP to 0.1 g.mm/m2.kPa.day. The oxygen permeability of soy protein isolate plasticized with 60% of glycerol films was in the range from 1 to 2 mm-cc/ m2-day, and the oxygen permeability value increases with the concentration of essential oils. Moreover, the soy protein films were analyzed for their microstructure using Scanning Electron Microscope (SEM). The films also characterize the interaction of all substances using Fourier Transform Infrared Spectroscopy (FTIR). In the last part of the study, a soy protein with cinnamon leaf oil film was applied to pack pork-balls. The packed pork meat balls were stored in the refrigerator for 3 weeks. The number of colony on 21st day was lower than the total plate count standard for foods (< 1*106 cfu/g). The research results show that soy protein with cinnamon leaf oil have the potency to be used in food industry to manufacture edible films and coatings. |
| Year | 2010 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. no.FB-10-13 |
| 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) | Rakshit, Sudip Kumar;Athapol Noomhorm; |
| Scholarship Donor(s) | RTG Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2010 |