Phenolic compounds found in canola : conversion to lignan and effects on globular protein properties
Rubino, Maria I.
Canola is one of the main sources of vegetable oil in Canada. The seeds of this crop contain approximately 40% edible oil and the meal produced after the oil extraction contains 40% protein... Therefore, canola represents not only a source of vegetable oil for human consumption, but also a valuable source of high quality protein. However, the use of canola meal is limited by the presence of high fiber and antinutritional factors such as glucosinolates, phytic acid and phenolic compounds (Thompson, 1990). This work deals with the phenolic compounds. Phenols in canola meal are responsible for bitter taste, brown colour and poor digestibility... The objective of this work was to understand the nature of the interactions between the phenolic compounds, specifically SA and SP, and the protein. Results provide a basis for developing an adequate procedure for extraction of phenolic compounds from the meal or the isolate, which would not alter the protein functionality or composition... The first part of this dissertation deals with the identification of the compound produced from SA. The identification of the product resulting from exposure of SP to alkaline conditions was not obtained in this investigation. The second part of this study is focused on the changes in SA at elevated pH values including evaluation of reaction rates under various atmospheres and in the presence of antioxidants... The last part of this work examined the effect of these phenolics on protein gelation, as determined by dynamic rheology. Using data from the binding studies, the role of protein phenolic interactions will be assessed and protein functionality can be evaluated. This information provides a means to understand how these compounds determine the systems where canola protein can be successfully incorporated.