Tuesday, 24 May 2005 - 1:55 PM
598

This presentation is part of: College Student Award Symposium sponsored by the Chromatography Forum of Delaware Valley

Microwave Extraction of Pectin and Characterization using High Performance Size Exclusion Chromatography

Halla Suleiman1, Hoa Chau1, and Marshall L. Fishman2. (1) USDA/ARS/ERRC, Wyndmoor, PA, (2) East. Reg. Res. Ctr., ARS, USDA, Wyndmoor, PA

The goal of the research was to develop a method whereby high-quality pectin could be extracted from orange albedo. Pectin was acid extracted from early Valencia orange albedo using rapid microwave heating under pressure. The extraction times ranged from 3-60 minutes, at a constant temperature. The pectin was then characterized for molar mass (M), radius of gyration (Rgz), and intrinsic viscosity (IVw). The characterization was obtained by High-Performance Size-Exclusion Chromatography with online light scattering and viscosity detection. The molar mass, radius of gyration, and intrinsic viscosity were the highest at the lower heating times, particularly at 3 minutes. The molar mass was 480,000 Daltons, the Rgz was 40.9 nm, and the IVw was 8.1 dL/g. As heating times increased the percentage of pectin recovered increased, whereas the M, Rgz, and IVw all decreased. Analysis of the Mark-Houwink plots showed that the pectin extracted at lower heating times was more compact and spherical. As heating times increased the pectin structure fragmented and became less compact.

Back to College Student Award Symposium sponsored by the Chromatography Forum of Delaware Valley
Back to The 37th Middle Atlantic Regional Meeting (May 22-25, 2005)