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International Journal of Food Engineering

Editor-in-Chief: Chen, Xiao Dong

4 Issues per year


IMPACT FACTOR 2013: 0.349

SCImago Journal Rank (SJR): 0.289
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Recovery of Polyphenolics from Apple Juice Utilizing Adsorbent Polymer Technology

Zaid S Saleh1 / Reginald Wibisono2 / Katja Lober3

1HortResearch, New Zealand

2HortResearch, New Zealand

3Hohenheim University, Germany

Citation Information: International Journal of Food Engineering. Volume 4, Issue 1, ISSN (Online) 1556-3758, DOI: 10.2202/1556-3758.1383, February 2008

Publication History

Published Online:
2008-02-12

A food grade divinylbenzene adsorbent resin was used to separate/recover plyphenolics from diluted apple juice concentrate. The work was carried out to investigate the effect of processing parameters on the adsorption process, to compare the efficiency of divinylbenzene adsorbent resin to that of ethylene glycol cross-linked polymethylmethacrylate adsorbent resin used in our previous study and to determine the effect of oxygen on the adsorption of polyphenolics process.A laboratory scale adsorption was determined by mixing weighed amounts of the polymer with a diluted apple juice concentrate at 10–60 oC and at pH values ranging from 2.0 to 3.9. At regular intervals, samples were withdrawn from the aqueous phase. Total phenolics, absorbance values at 280 and 420 nm, and the amounts of individual phenolics remaining in the liquid phase were determined. The analytical data were fitted to the Langmuir and Freundlich isotherms.Findings from this study are in agreement with Kammerer et al. (2006) but, in contrast to previous studies, the pH value significantly affected the adsorption onto the resin. HPLC analyses revealed different affinities of individual compounds, which enabled selective enrichment of certain phenolics in the liquid phase or on the sorbent surface. HPLC profiling showed that the polyphenolics recovered did not differ significantly from those in the original apple extracts. This has confirmed that there is minimal damage during processing. The major losses in the process were due to polyphenols not binding to, or not being recovered from, the adsorbent. Optimization of the process would enable the losses to be minimized and up to 80% of the polyphenolics could be recovered in the extracts.Desorption studies were performed using a resin with known amounts of adsorbed phenolic compounds. Elution was carried out by an automated pressurized liquid extraction system, studying the effects of temperature (40–180 oC) and solvents (water, ethanol, methanol). Again, individual compounds behaved differently, depending on their hydrophobicity. Therefore, a systematic change of parameters for the adsorption and desorption process can be helpful for the recovery of purified plant extracts enriched in certain target compounds.

Keywords: polyphenolics; recovery; adsorption; desorption; resin

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