Sustainable sunflower processing – I. Development of a process for the adsorptive decolorization of sunflower [Helianthus annuus L.] protein extracts

Publication Type

Journal contribution (peer reviewed)

Authors

WEISZ, G.M., SCHNEIDER, L., SCHWEIGGERT, U., KAMMERER, D.R., CARLE, R.

Year of publication

2010

Published in

Innovative Food Science & Emerging Technologies

Editor

D. Knorr, M. Hendrickx

Pubisher

Elsevier

Band/Volume

11/

Page (from - to)

733-741

Keywords

Absorption

A novel process for the production of light-colored sunflower protein isolates was developed, combining mild-acidic protein extraction with adsorptive removal of phenolic compounds. Four commercial food-grade adsorbent and three ion exchange resins were tested with regard to their affinity towards polyphenols. Amberlite™ XAD 16HP and FPX 66 showed optimal decolorization of the sunflower crude extracts. In contrast, ion exchange resins exerted maximal binding of monomeric phenolic compounds, but were less effective in removing colored compounds. Adsorption behavior of individual resins was assessed by adding resin to protein extracts varying the amounts of resin, protein concentration of the solutions and temperature. Furthermore, a D-optimal experimental design was applied to optimize adsorptive polyphenol removal from sunflower protein extracts using a styrene-divinylbenzene copolymer. Adsorption isotherms were determined for 5-O-caffeoylquinic acid and total phenolics, respectively. Optimal conditions were deduced from experiments at different temperatures, with different flow rates and extract concentrations. Finally, adsorbent and ion exchange resin columns were connected in series and successfully applied to produce light-colored sunflower protein on a pilot scale under the conditions optimized in laboratory experiments, thus demonstrating that this technology can easily be integrated into existing process lines.