Evaluation of Ion Exchange and Sorbing Materials for Their Adsorption/Desorption Performane towards Anthocyanins, Total Phenolics, and Sugars from a Grape Pomace Extract

Abstract

Byproducts of winery industries are treated, in many cases, as useless wastes constituting not only a major disposal problem but also not providing any additional profit to the industries. However, these byproducts could be utilized as a source of various phenolic compounds, such as anthocyanins, that could be used as nutraceuticals or natural colorants. Nine materials were tested and evaluated for their ability to retain and elute anthocyanins, total phenolics, and sugars from a grape pomace extract. The materials tested were the ion exchange Amberlite IRA 400 Cl−, Lewatit TP 208 and Lewatit TP 260, and the sorbing Chromosorb G-HP, Amberite XAD 2, Zeocros CA 150, Chemviron Carbon, Oasis HLB (hydrophilic-lipophilic balance) and Isolute C8 end-capped (EC). The two materials with the higher anthocyanins recovery rate, Oasis HLB and Isolute C8 (EC), were further examined for their anthocyanin capacities which were calculated as 5.76 mg·cm−3 and 3.06 mg·cm−3 respectively. Furthermore, their behavior pattern towards anthocyanins of various molecular weights was investigated using a liquid chromatography coupled with mass spectrometry (LC-PDA-MS) system.

Keywords

• grape pomace
• anthocyanins
• total phenolics
• sugars
• solid-phase extraction
• mass spectrometry