Pomegranate (Punica granatum) is one of the first cultivated foods in the world. Although pomegranates have been extensively used in the folk medicine of many cultures, other properties have been recently claimed such as antioxidant activity and beneficial effects against several diseases. Indeed, the number of scientific publications related to the health benefits of pomegranate has been considerably increased in recent years providing the scientific basis for some uses of pomegranate in traditional medicine [1]. Considering the health promoting effects of the pomegranate juice consumption and the overproduction of fresh fruits in some Countries, the interest of producers and consumers towards the production of nutraceuticals based components of the pomegranate is gradually increased in the last decade. An overview of recent investigations related to the pomegranate juice processing by using membrane-based operations, including ultrafiltration (UF) and osmotic distillation (OD), is given. In particular, clarification, concentration and fractionation of the pomegranate juice have been studied in order to preserve the antioxidant activity of the fresh juice, to obtain high quality concentrated juices and fractions of interest for nutraceutical applications. Modified poly(ether ether ketone) and polysulfone hollow fibre membranes, with high water flux and molecular weight cut-off, were prepared via the dry-wet spinning technique through the phase inversion process and characterized by scanning electron microscopy, water permeability and dextran rejection. The prepared membranes were used to clarify pomegranate juice with the aim to preserve the phenolic fraction and to obtain high permeation fluxes [2]. The concentration process performed by OD allowed clarified juice to be concentrated without modifying the main physico-chemical parameters of the product. A 3.2-fold concentration of total soluble solids was achieved by using OD without any back diffusion of solute and burned off flavor due to the hydrophobic nature of the membrane [3]. A fractionation step of the pomegranate clarified juice was investigated by using commercial flat-sheet UF membranes in order to separate glucose and fructose, which are the main sugars of the raw pomegranate juice, from bioactive compounds. Suitable membranes exhibiting high permeation fluxes, high retention towards polyphenols and anthocyanic compounds and low retention towards sugars were identified. [1]M.I. Gil, F.A. Tomas-Barberan, B. Hess-Pierce, D.M. Holcroft, A.A. Kader, Antioxidant activity of pomegranate juice and its relationship with phenolic composition and processing, Journal of Agricultural and Food Chemistry, 48 (2000) 4581-4589. [2]A. Cassano, C. Conidi, F. Tasselli, Clarification of pomegranate juice (Punica Granatum L.) by hollow fibre membranes: analyses of membrane fouling and performance, Journal of Chemical Technology and Biotecnology, 90 (2015) 859-866. [3]A. Cassano, C. Conidi, E. Drioli, Clarification and concentration of pomegranate juice (Punica granatum L.) using membrane processes, Journal of Food Engineering, 107 (2011) 366-373.
Membrane operations in pomegranate juice processing: potentialities and perspectives
Cassano A;Tasselli F;Conidi C;Drioli E
2015
Abstract
Pomegranate (Punica granatum) is one of the first cultivated foods in the world. Although pomegranates have been extensively used in the folk medicine of many cultures, other properties have been recently claimed such as antioxidant activity and beneficial effects against several diseases. Indeed, the number of scientific publications related to the health benefits of pomegranate has been considerably increased in recent years providing the scientific basis for some uses of pomegranate in traditional medicine [1]. Considering the health promoting effects of the pomegranate juice consumption and the overproduction of fresh fruits in some Countries, the interest of producers and consumers towards the production of nutraceuticals based components of the pomegranate is gradually increased in the last decade. An overview of recent investigations related to the pomegranate juice processing by using membrane-based operations, including ultrafiltration (UF) and osmotic distillation (OD), is given. In particular, clarification, concentration and fractionation of the pomegranate juice have been studied in order to preserve the antioxidant activity of the fresh juice, to obtain high quality concentrated juices and fractions of interest for nutraceutical applications. Modified poly(ether ether ketone) and polysulfone hollow fibre membranes, with high water flux and molecular weight cut-off, were prepared via the dry-wet spinning technique through the phase inversion process and characterized by scanning electron microscopy, water permeability and dextran rejection. The prepared membranes were used to clarify pomegranate juice with the aim to preserve the phenolic fraction and to obtain high permeation fluxes [2]. The concentration process performed by OD allowed clarified juice to be concentrated without modifying the main physico-chemical parameters of the product. A 3.2-fold concentration of total soluble solids was achieved by using OD without any back diffusion of solute and burned off flavor due to the hydrophobic nature of the membrane [3]. A fractionation step of the pomegranate clarified juice was investigated by using commercial flat-sheet UF membranes in order to separate glucose and fructose, which are the main sugars of the raw pomegranate juice, from bioactive compounds. Suitable membranes exhibiting high permeation fluxes, high retention towards polyphenols and anthocyanic compounds and low retention towards sugars were identified. [1]M.I. Gil, F.A. Tomas-Barberan, B. Hess-Pierce, D.M. Holcroft, A.A. Kader, Antioxidant activity of pomegranate juice and its relationship with phenolic composition and processing, Journal of Agricultural and Food Chemistry, 48 (2000) 4581-4589. [2]A. Cassano, C. Conidi, F. Tasselli, Clarification of pomegranate juice (Punica Granatum L.) by hollow fibre membranes: analyses of membrane fouling and performance, Journal of Chemical Technology and Biotecnology, 90 (2015) 859-866. [3]A. Cassano, C. Conidi, E. Drioli, Clarification and concentration of pomegranate juice (Punica granatum L.) using membrane processes, Journal of Food Engineering, 107 (2011) 366-373.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
