Title: Extraction of Lipids from Flax Processing Waste Using Hot Ethanol Authors
Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 5, 2007
Publication Date: February 9, 2008
Citation: Holser, R.A., Akin, D.E. 2008. Extraction of Lipids from Flax Processing Waste Using Hot Ethanol. Industrial Crops and Products. Interpretive Summary: Large amounts of waste generated during processing flax fiber limits the cost effectiveness of production of this natural fiber. Some of these waste materials have been reported to contain potential value-added co-products, such as lipids from the cuticle. Researchers developed a method using hot ethanol to extracts a mixture of lipids from three flax processing waste streams, including wax esters and a mixture of compounds similar to policosinols. This research could result in production of value-added wax materials from waste streams and futher augment the cost effectiveness of flax and natural fiber industries.
Technical Abstract: The cuticle of flax stems contain lipids that provide a protective barrier to pathogens and control moisture loss. These lipids include wax esters and long chain fatty alcohols or policosanols. Cuticle fragments generated during several different fiber processing operations retain these lipid compounds that represent a potential co-product. Samples of flax shives (i.e., lignified core tissues), processing dust, and cuticular fractions recovered from enzyme retting waste water were extracted in the laboratory with hot ethanol to remove the lipid compounds. Ethanol extracts were analyzed by gas chromatography to determine the amount and type of lipids recovered. The results demonstrated that hot ethanol effectively extracted the lipid compounds from cuticle fragments in all these samples. When the extract was cooled, the longer chain wax esters (i.e., chain length of 44 carbon atoms or larger) precipitated and could be separated from the shorter chain lipid components (i.e., fatty alcohols and aldehydes less than 44 carbons). Similar results were obtained using absolute ethanol or 95% ethanol (aqueous). This technique provides a very economical method to recover lipid fractions as potential value-added co-product from flax processing waste.