Extraction of pectin from sugar beet pulp by high hydrostatic pressure and invest igation of extraction efficiency and extract characteristics.

Kaya, Burcu
Food industry produces huge amount of food waste after food processing. The food wastes could include significant amount of functional ingredients that have valorization potential. The techniques utilized to obtain functional compounds from food wastes are named as valorization. One of the important wastes of food industry is sugar beet pulp which is the waste of sugar processing. Utilizing this pulp for various applications has been very common recently. In this study, sugar beet pulp pectin was extracted using conventional extraction and high hydrostatic pres sure (HHP) assisted extraction. HHP was applied prior to extraction to ease detachment of pectin from cell wall. Different pressures (250, 350, 450 MPa) at 40°C for 5 min, two different extraction temperature (80°C, 90°C) and three different time (3, 4, 5 h) combinations were applied. Moreover, conventional extraction (CE) was compared with the results of HHP assisted extraction. Extraction yield, degree of esterification (DE), galacturonic acid content (Gal-A), rheological properties and water holding capacity (WHC) of pectin solutions were investigated. Obtained pectin was also investigated with FTIR Spectroscopy for structural elucidation. In addition, water holding capacity experiments were conducted by using Time Domain NMR Relaxometry. Extraction yield was almost doubled at HHP assisted extraction as 12.23±0.13% regarding 6.43±0.07% CE yield. HHP assisted extraction showed increasing DE values at prolonged extraction times but overall change was between 32-38% which was l ow enough to not reflect in viscosities of extracted pectin solutions. Change in viscosities were mostly insignificant (p>0.05). Gal-A decreased with increasing pressure, but it was still in safe limit regarding 60-65% Gal-A requirement of FAO. WHC was held insignificantly changed (p>0.05) at HHP assisted extraction by adjusting pressure considering the same temperature-time of CE. The results suggest that HHP assisted extraction is highly effective on increasing yield and modifying structural and functional properties of extracted pectin.
Citation Formats
B. Kaya, “Extraction of pectin from sugar beet pulp by high hydrostatic pressure and invest igation of extraction efficiency and extract characteristics.,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Food Engineering., Middle East Technical University, 2020.