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Selecting Ultrafiltration Membranes for Fractionation of High Added Value Compounds from Grape Pomace Extracts

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Selecting Ultrafiltration Membranes for Fractionation of High Added Value Compounds from Grape Pomace Extracts Received: 30 October 2018 y Accepted: 20 May 2019 y Published: 29 July 2019 DOI:10.20870/oeno-one.2019.53.3.2343 VINE AND WINE OPEN ACCESS JOURNAL Selecting ultrafiltration membranes for fractionation of high added value compounds from grape pomace extracts Sami Yammine 1, Robin Rabagliato 1, Xavier Vitrac 2, Martine Mietton Peuchot 1 and Rémy Ghidossi 1 1Université Bordeaux, ISVV, Unité de recherche Œnologie, EA 4577, USC 1366 Inra, Bordeaux INP, 33882 Villenave d’Ornon, France 2Laboratoire Phenobio SAS, Centre Montesquieu, 1 allée Jean Rostand, 33650 Martillac, France Corresponding author: [email protected] ABSTRACT The purpose of the current study is to investigate the use of ultrafiltration membrane for the fractionation of phenolic compounds from subcritical water grape pomace extract and the separation of these compounds from other co-extracted components. The extract was assayed in a cross-flow apparatus against eleven membranes with molecular weight ranging from 100 to 2 kDa. Monitoring of the process was executed by determining performance parameters and retention coefficients of proteins, polysaccharides, sugars, phenolic and anthocyanin classes. Results indicated that retention of solutes was affected, not by size exclusion, but primarily by severe fouling phenomena due to polar solutes adsorption on the membrane surface. With the exception of the separation obtained between polymeric and monomeric proanthocyanidins, polysulfone membranes were not able to fractionate phenolic classes. Membranes starting of 20 kDa and over retained high percentages (>60%) of polysaccharides and proteins. KEYWORDS ultrafiltration, grape pomace, proteins, pectins, phenolic compounds A BBREVIATIONS AUC Area under the curve - CCD charge-coupled device - Cif concentrations of compound in feed - Cip concentrations of compound in permeate DAD Diode - Array Detector - DW Dry weight - HPLC High performance liquid chromatography - J p permeate flux during extract filtration - J w pure water flux - MF Microfiltration - MS Mass spectrometer - MW Molecular Weight - MWCO Molecular weight cut off - NF Nanofiltration - ORAC - P pressure - PEG Poly Ethylene Glycol Ra Fouling resistance - Ri Initial resistance - Rm membrane resistance RO Revers eOsmos is - R t total resistance - SE Standard error - TMP Trans - Membrane Pressure - UF Ultrafiltration - UPLC Ultra High - pressure Liquid -Chromatography - UV Ultra violet - V 0 initial feed volume - V R retention volume - VRF volume - reduction vector - µ p dynamic - viscosity of the extract - µ w dynamic viscosity of water OENO One 2019, 3, 487-497 © 2019 International Viticulture and Enology Society - IVES 487 Sami Yammine et al. INTRODUCTION polyphenolic compounds without utilizing any organic solvent. We have previously optimized A significant quantity of grape derivatives are the extraction of fermented grape pomace using generated worldwide by the wine industry. These subcritical water extraction (Yammine et al. , byproducts are an important source of 2015). To realise the purification of the crude antioxidant molecules such as polyphenols, extract, several organic membranes with -1 ranging from 2.5 to 7.8 g 100 g dry weight differential molecular weight cut off of 100 kDa (DW) (Spigno and De Faveri, 2007). Grape to 2 kDa were tested. The performance of the byproducts contain quantities of different process in terms of retention, permeate flux and phenolic compounds, important for their role in transmembrane pressures (TMP) in a UF plant physiology and are regarded as noteable apparatus was evaluated. Conditions consisted of components of human nutrition. The latter idea is constant temperature and circulation flow rate. backed by numerous studies indicating Retention percentages of phenolic acids, interesting antioxidant capacity; cardiopro- stilbenes, anthocyanins, monomeric flavan-3-ols tective, neuroprotective and anticancer (Craft et and polymeric flavan-3-ols were obtained with al. , 2012; Kähkönen and Heinonen, 2003; different membranes. Quideau et al. , 2011; Stintzing et al. , 2002). MATERIALS AND METHODS The use of ultrafiltration membrane (UF) for plant extract purification has been little reported; 1. Subcritical water extraction Tsibranska et al. (2011); Galanakis et al. (2013); In the extraction system, a HPLC pump Díaz-Reinoso et al. (2009); Santamaría et al. (Shimadzu LD-AC10) was used for deionized (2002) assayed different tubular polymeric water delivery and controlling the pressure of the membrane sequences in order to fractionate system. A pressure transducer (Davidson, Druck) phenolics (gallic acid, catechin and gallates) and thermocouple (Caveland Electric) were recovered from defatted milled grape seeds, installed in the custom-made high-pressure using acetone–water mixtures on the basis of vessel to monitor both pressure and temperature molecular weight (MW). Díaz-Reinoso et al. of the system. Extract was collected in an inerted (2009) processed to concentrate, aqueous vessel after passing through an ice bath. In each extracts from pressed distilled grape pomace by run, red Dunkelfelder pomace (70g), supplied by nanofiltration (NF) membranes. The five tested the university of Changins, was loaded into the ceramic NF membranes were suitable for high-pressure vessel, which can contain 325 cm 3 concentration purposes. The phenolic content in of material. The vessel was placed in an oven at retentates was increased by factors of 3–6. While a predetermined temperature of 150 °C. The Galanakis et al. (2013) suggested that the outlet valve of the extraction vessel was then separation of phenolic compounds recovered closed and the system was pressurized to the from winery sludge is achievable using three desired 25 bars at a constant flow rate. The water ultrafiltration organic membranes (100 kDa, flow rate was adjusted at 20 mL/min using a 20 kDa, 1 kDa). The authors established that metering valve on the HPLC pump. After 3 L of polysulfone membranes were able to separate extraction, the solution which was collected in an phenolic compounds from pectin fractions. They inerted sampling vessel and the pomace were could not fractionate different phenolic classes then stored at 4 °C for further analysis and and sugars (reducing or not) as they were membrane separation. retained even in high percentages at 100 kDa. By contrast, the application of a non-polar 2. Experimental analysis and membranes fluoropolymer membrane in the border of UF and NF (1 kDa) could provide a successful UF experiments were performed in a pilot unit methodology to separate different phenolic (Figure 1), equipped with a Sepa® CF II classes. Recently Zagklis and Paraskeva (2015) Membrane Cell System (GE Osmonics, Minnetonka, MN, USA) featuring an effective proposed a purification method for the separation 2 of grape marc phenolic compounds coupling UF membrane area of 0.0153 m . The temperature was maintained at 20 ± 0.5 °C by using a thermal (100 kDa) and NF 480 Da) with resin -1 adsorption/desorption. bath. Permeate flux was determined at a 2 m s of crossflow velocity, by weighing the amount of This study aims to determine the feasibility of permeate with a balance, connected to a using UF to separate and concentrate computer. Weight and pressure values were 488 © 2019 International Viticulture and Enology Society - IVES OENO One 2019, 3, 487-497 ! ! ! ! ! ! ! ! ! ! ! FIGURE 1. Flow sheet of the experimental apparatus: 1. thermal bath, 2. feed tank, 3. temperature probe, 4. high-pressure pump, 5. security valve, 6. valves, 8. pressure probes, 9. membrane cell system, 10. ! ' ' % % % % % % % % % % % % % valves,, 11. pressure control valve, 12. balance ! % % % % % % % % % % % % ! % % % ! % % % % % % % % % % ! r ecorded every second by an electronic system. The duration of each experiment varied ! The eleven commercial UF flat-s!heet membranes according to the desired value of volume ! were acquired from the m! anufac! turers ; Table 1 r edu ction fa ctor ( VRF) to b e re ached . Th is ! lists th eir charac teristics. Only new membranes p arameter is d efin ed b y: were used throughout the experim! ent. !" !"# ! ! !" 3. Membrane process ! The membranes were !preconditi one d wit h wher e V0 is th e ini tial fee d vo lume and VR is the he extract ! deionized wa ter for 60 m in a! t 20 °C u sin g re te ntio n volu m e, t ha t i s he extrac t volume he extract 5 -1 transmembrane pressure !5.10 Pa and 2 ms of re maining in the stora ge ve ss el ( V R = V0 − VP). ! crossflow velocity. Water per!meability was ! For t he MWC O m em brane s rang ing f rom determine d f or four pressur es b! etw een 10 5 Pa ! 5 50 kDa to 100 kDa the permeate flux was and 5.10 Pa during ! the last 20 m in of ex pr esse d at a VRF = 1 0, w h ich implies 1 .8 L of ! preconditioning usi ng the slope! of the pl ot o f permeate was obtained. While for lower MWCO permeate weight recovere!d, again!st ti me. ! mem branes of 20 t o 2 k Da , d ue to lower Immediately after precon! ditioni!ng , a tri al wi th f il tra tio n fl u xe s , p ermea te fl ux w a s expresse d at a VRF = 2 and a retentate 1L was obtained. The ! grape pomac e extract wa!s filtere!d. The filtra t ion experiments were conducted at the natural pH of samples of raw material and permeate collected ! th e extract (3.7) in tang!ential c!rossflow m od e wer e imme dia tely froz e n an d kept a t − 20 °C with the feed stream flowing tangential to the until analyzed. To measure membrane selectivity ! fo r a s olute, th e observe d retention was membrane surface. The !operating metho d w as ! calculated, as shown in the following batch concentration m!ode ; the retentate or expression: !"#!"# concentrate stream was flowed back to the feed !" ! ! ! ! !"" tank, while the permeate stream was collected !"#!"# separately and not recirculated to the storage where Ri is the observed retention of compound vessel.
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