ARS | Publication request: Utilization of pectin extracted sugar beet pulp for composite application

Submitted to: Journal of Biobased Materials and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 2, 2012
Publication Date: March 26, 2012
Citation: Liu, B., Zhang, J., Liu, L.S., Hotchkiss, A.T. 2012. Utilization of pectin extracted sugar beet pulp for composite application. Journal of Biobased Materials and Bioenergy. 6:1-8.

Interpretive Summary: The US beet sugar industry generates million of tons of sugar beet pulp (SBP) annually from which pectin, a food additive was extracted. We co-extruded pectin-extracted SBP and polylactic acid (PLA), and evaluated the mechanical properties of the resultant composite membranes. It was found that SBP residues obtained after pectin extraction, still contain a certain level of pectin that can be compounded with PLA to make packaging membranes with suitable mechanical properties. The present study provides a new strategy to make cost-affordable, biodegradable packaging materials. The beet sugar growers and processors will benefit from this research.

Technical Abstract: Sugar beet pulp (SBP) is the residue left after beet sugar extraction. SBP contains ~25% pectin and is an important source for pectin. However, sugar beet pectin does not have good gel-forming properties and complete extraction of pectin is not typically performed due to the low quality of the galacturonic acid-containing polysaccharide remaining following commercial pectin extraction. This study was conducted to determine the level of residual pectin needed for making SBP composites and the effects of pectin content on the properties of the resulting composites. In this work, the pectin extracted SBP (PE-SBP) was recombined with pectin to prepare SBP composites. The compounding of pectin and PE-SBP was conducted using a twin-screw extruder, and water and glycerol were used as plasticizers. Pectin was plasticized during extrusion and behaved like a binder or matrix for the pectin/PE-SBP compounds, depending on pectin content. Mechanical and thermal properties of the compounds were studied and the results showed that utilization of the extracted SBP as a resource for plastic materials is possible.