Evaluation of Polyphenol Content and Lipoxygenase Activity in Selected Oil Cakes in Terms of Their Valorization

Abstract

Oil cakes are pomace that is a by-product of pressing oil from oilseeds. Due to the content of bioactive ingredients, there is more and more talk about their valorization through use in human and animal nutrition as well as microbiological processes aimed at the biosynthesis of biosurfactants, enzymes and fragrance compounds. The aim of this research was a qualitative assessment of selected oil cakes (linseed, rapeseed, hemp, safflower and camelina oil cakes) in the context of their potential use in microbiological cultures aimed at the biosynthesis of green note aroma compounds. The scope of the research included the analysis of the fatty acid composition of the lipid fraction of oil cakes as well as the determination of lipoxygenase activity and the polyphenol content in the extracts of these raw materials. Chromatographic analysis of the lipid fraction showed that hemp and safflower cakes had the highest content of polyunsaturated fatty acids. PUFAs constitute 67.18 ± 2.2% and 73.72 ± 1.8% in their extracts, respectively. Hemp cake extracts were also characterized by the highest lipoxygenase activity—76.4–1.2 U/mL with a low content of phenolic compounds at the level of 0.116 ± 0.005 mg GAE/mL of extract.

Keywords

• oil cakes
• lipoxygenase
• waste valorization
• green note aroma compounds