Optimisation and Characterisation of the Cross-Linking Reaction Between Plant Proteins Using Different Strains of Laccase and Transglutaminase
| dc.contributor.advisor | Le, Thao | |
| dc.contributor.author | Al-Shaikhli, Yusur Hisham Saleh | |
| dc.date.accessioned | 2023-06-23T00:38:20Z | |
| dc.date.available | 2023-06-23T00:38:20Z | |
| dc.date.issued | 2023 | |
| dc.description.abstract | Plant proteins have recently gained interest due to the growth in global population and the need for more sustainable, lower cost, and health beneficiary protein sources. However, there is a limitation in the application of plant-based proteins because of their poor functionalities such as solubility, and lower levels of essential amino acids and digestibility. There is a need to modify the protein structure to improve its functional and nutritional quality using various methods such as heat or enzymic treatment. In this research, the optimization of enzymic modification will be done on lupin and pea as well as lupin and soy. The enzymes used to cross-link the selected proteins are laccase and transglutaminase in which different conditions e.g., pH change, incubation time, incubation temperature, enzyme concentrations, and protein concentrations were applied to optimise the cross-linking reaction. The results showed a limitation in the cross-linking of lupin and pea which could be due to the low solubility of pea. Nevertheless, there was a change to the cross-linking of soy and lupin proteins where it showed the cross-links more clearly on SDS-PAGE gels. The optimal conditions were chosen to be upscaled and multiple physicochemical tests were done to examine the effect of cross-linking on the proteins. Such as examining the emulsion properties, which showed that the emulsion ability of enzymatically treated proteins was not significantly different from each other; however, proteins treated with TG had higher emulsion stability compared with proteins treated with laccase. The particle size was also examined; the diameter size was found to be smaller in the mixture treated with laccase (LA1) for 20 hours at 20°C, while the mixture treated with laccase and ferulic acid (LA1+FA) for 1 hour at 20°C had the highest particle diameter as well as the lowest surface area based on particle diameter. Further tests such as amino acid analysis, digestibility, and allergenicity are required to be done but could not be completed due to the time limit, COVID-19 restrictions, and broken instrument. | |
| dc.identifier.uri | https://hdl.handle.net/10292/16307 | |
| dc.language.iso | en | |
| dc.publisher | Auckland University of Technology | |
| dc.rights.accessrights | OpenAccess | |
| dc.title | Optimisation and Characterisation of the Cross-Linking Reaction Between Plant Proteins Using Different Strains of Laccase and Transglutaminase | |
| thesis.degree.grantor | Auckland University of Technology | |
| thesis.degree.name | Bachelors of Science (Honours) |