Effects of Atmospheric Cold Plasma Treatment on Canola Protein Structural and Functional Properties
Creators: Arif, Muhammad Faisal
Publisher: name: University of Alberta Library
Year: 2024

<p>Canola meal contains a considerable concentration of protein after oil extraction, and it is a potential alternative to other plant proteins because of its functional properties and well-balanced amino acid composition. However, canola meal contains undesirable compounds such as phenolic compounds including sinapine, the principal anti-nutritional compound among all phenolic compounds. Atmospheric cold plasma (ACP) is a nonthermal technology, which can potentially improve the functional properties of proteins. ACP is capable to degrading the antinutritional compounds in canola protein concentrate (CPC), making it more suitable for various applications in the food industry. In this research, the application of ACP treatment resulted in 74 and 43.6% reductions in total phenolic compounds and sinapine concentration of CPC, respectively. Moreover, the ACP treatment led to enhanced functional properties of canola protein including improved solubility, emulsification, and foaming properties, accompanied by notable structural modification. The solubility of CPC was dependent on the pH and the ACP treatment time. The ACP treatment improved the emulsifying properties. The exposure to ACP unfolded the CPC structure as demonstrated by the Fourier transform infrared spectroscopy analysis. After ACP treatment, the β-sheets and random coil structures of CPC increased, but the β-turn and α-helix decreased. The structural changes induced by ACP treatment, with increased random coil, β-sheets, and decreased β-turn, and α-helix can affect different canola protein functionalities by potentially improving solubility and enhancing emulsification properties. The second part of this research aimed to determine the combined effect of ACP treatment with pH shifting to improve the quality of canola protein and degrade the antinutritional compounds. The CPC underwent ACP treatment for a duration of 10 min at pH levels of 6, 8, and 10, and subsequently the pH was adjusted to 7. The combined ACP treatment and pH shifting led to a substantial reduction in the sinapine from 94.6 to 12.6 µg/mL after 10 min. Also, the solubility of CPC was increased after the pH shifting with ACP treatment, especially in alkaline conditions. The CPC treated by ACP for 10 min at pH 10, followed by pH shifting to 7 resulted in a significant increase in emulsification activity. Additionally, the emulsification stability of the treated samples was observed to be 54.5%, showing a substantial improvement compared to the control. A similar trend was observed for foaming capacity and foaming stability, wherein their values increased significantly at pH 10 following the combined treatment of ACP and pH shifting. These findings highlighted the efficacy of the ACP treatment and pH shifting combination in enhancing the emulsification and foaming properties of CPC, particularly at a pH level of 10.  The results from this study indicate the potential of the ACP treatment on improving the properties of canola protein, and the degradation of antinutritional compounds from canola protein concentrate. </p>