Clarification Of Pomegranate Juice Research Articles

Pomegranate Juice Clarification Using Ultrafiltration: Influence of the Type of Variety and Degree of Ripeness

Fruit consumption guarantees the supply of most of the necessary nutrients for a complete and balanced diet, as it is a relevant source of vitamins, minerals, and antioxidants. In particular, pomegranate has very interesting medicinal properties, such as an anti-inflammatory effect and the protection of the cardiovascular system, among others. During pomegranate juice production, it appears cloudy and must be clarified to remove suspended solids such as colloids and high-molecular weight tannins. The membrane clarification process is a cost-effective alternative to the conventional methods, resulting in a high-quality product. In this work, the clarification of pomegranate juice using the Triple System Model F1 membrane module was carried out for the Mollar and Wonderful varieties with early and late maturity. Three ultrafiltration membranes with different molecular weight cut-off and different chemical compositions were used. The rejection coefficient and permeate flux (which represent the selectivity of the membranes and the process efficiency, respectively) were measured. GR-40PP showed the best results in terms of membrane selectivity and process efficiency, achieving adequate physicochemical juice parameters. Regarding the comparison of the maturity degree, in general terms, the Mollar variety showed better results. Ripe pomegranates showed greater selectivity, while the process efficiency was higher for the early samples.

Effect of Pre-treatment on Aggregation, Biochemical Quality and Membrane Clarification of Pomegranate Juice

Effect of Pre-treatment on Aggregation, Biochemical Quality and Membrane Clarification of Pomegranate Juice

Simulation of the Effect of Centrifugation on Membrane Efficiency by Using Computational Fluid Dynamics During the Clarification of Pomegranate Juice

Simulation of the Effect of Centrifugation on Membrane Efficiency by Using Computational Fluid Dynamics During the Clarification of Pomegranate Juice

Permeate flux prediction in the ultrafiltration of fruit juices by ARIMA models

The quantitative prediction of phenomena responsible of flux decline is of great interest in membrane operations. In this work the application of ARIMA models was investigated to predict the permeate flux in the ultrafiltration (UF) of fruit juices during 6h of continuous operation. Models were constructed with the filtration data of fruit juices (bergamot, kiwifruit and pomegranate) clarified with different membranes.The ARIMA 211 model showed the lowest value of root mean squared error (RMSE) (0.3891) and a mean absolute percentage error (MAPE) of 4.9476; the model was found to be very successful in predicting the flux decline over time with a prediction of 99.96% (R2adj, R-squared adjusted by degree of freedom) in the clarification of bergamot juice. The ARIMA 111 model predicted 99.61% of experimental values (R2adj) with the lowest values of RMSE (0.2516) and MAPE (1.9566) in the clarification of kiwifruit juice. The ARIMA 212 model fitted 99.14% of experimental data (R2adj) in the clarification of pomegranate juice with lower values of RMSE (0.2768) and MAPE (2.2613). The proposed approach offers a simple alternative for the prediction of the permeate flux since modeling does not require information on feed solution, membrane material, membrane configuration and operating conditions.

Simulation of the Effect of a Baffle Structure on Membrane Efficiency Using Computational Fluid Dynamics during the Clarification of Pomegranate Juice

Simulation of the Effect of a Baffle Structure on Membrane Efficiency Using Computational Fluid Dynamics during the Clarification of Pomegranate Juice

Modeling of turbulent cross flow microfiltration of pomegranate juice using hollow fiber membranes

A mathematical analysis of the permeate flux decline during microfiltration of fruit juice with hollow fibers under turbulent flow is presented. Impact of complex fluid flow phenomena on mass transfer is analyzed. A comprehensive analytical model for developing concentration boundary layer was formulated from first principles using integral method. Attempts to model the system considering constant boundary layer thickness (film theory) is inaccurate for developing boundary layer. Gel resistance parameter depending on juice characteristics has significant impact on permeate flux. Specific gel layer concentration has insignificant effect on system performance under total recycle mode but important for batch mode. Theoretical results were compared with experiments in clarification of pomegranate juice with poly(ether ether ketone) and polysulfone hollow fiber membranes. The physical parameters of complex mixture were evaluated by optimizing of the flux profiles in total recycle mode of operation and were successfully applied for prediction of batch mode performance. © 2014 American Institute of Chemical Engineers AIChE J 60: 4279–4291, 2014

Clarification of pomegranate juice (Punica Granatum L.) by hollow fibre membranes: analyses of membrane fouling and performance

AbstractBACKGROUNDMembrane based clarification of fruit juices has become a popular unit operation in modern fruit juice processing industries. In this work 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. The effect of transmembrane pressure and axial feed velocity on permeation flux and hydraulic resistances of the prepared membranes was investigated.RESULTSPermeate fluxes increased by increasing the axial velocity of the juice. The flow–pressure curves followed the gel‐polarization model. All resistances, with the exception of the membrane resistance increased by increasing the operating pressure and decreased with the axial feed velocity. Polysulfone membranes exhibited higher steady state permeate flux (47 L m−2 h−1) and lower rejection towards flavonoids (24.1%) and phenolic compounds (25.1%) in selected operating conditions.CONCLUSIONPolysulfone membranes were suitable for preserving phenolic compounds in the clarification of pomegranate juice. For these membranes operating conditions giving maximum permeation fluxes and minimum fouling index were identified. © 2014 Society of Chemical Industry

Clarification of Pomegranate Juice at Industrial Scale

The effects of conventional and membrane clarification processes on some physicochemical properties of pomegranate juice such as color, turbidity, Total Soluble Solids (TSS), Total Phenolic Content (TPC), antioxidant activity and bioactive compounds (anthocyanins, ellagitannins and ellagid acid) were evaluated. Changes in color parameters such as absorbance at 520 nm (A520, red color), Total Color Density (TCD) and Browning Index (BI), as well as TPC were negatively influenced by bentonite or albumin concentration in batch processes. However, both microfiltration (MF) and ultrafiltration (UF) processes at the applied conditions did not cause any significant differences on the levels of A520, BI, TPC, and other parameters determined as part of the evaluation study. Moreover, the permeate flux in MF were higher than in UF, which is preferable for commercial application of tangential filtration technology in pomegranate juice industry. MF-clarified juice had physicochemical and nutritional properties similar to those of fresh juice.

Clarification of pomegranate juice by ultrafiltration: study of juice quality and of the fouling mechanism

Introduction . Ultrafiltration (UF) is a single-unit operation for the clarification and fining of fruit juices. The purpose of the UF is to remove suspended solids as well as haze-inducing and turbidity-causing substances to obtain a clear juice during storage. Specifically, the polymerization of phenolic compounds and their interaction with other components (e.g. , proteins) could cause a haze complex and turbidity in fruit juices, which can foul the ultrafiltration membrane. Materials and methods . Fresh pomegranate juice was clarified by the ultrafiltration process on a laboratory scale. In experimental tests performed according to the total recycle and the batch concentration mode, the effects of transmembrane pressure (TMP) and enzyme pre-treatment on permeation flux and quality of juice were studied. Results . With the total recycle mode, the effect of TMP on the color and clarity of clarified pomegranate juice was significant. The initial color of the raw pomegranate juice was reduced from 74% to 33% and the clarity decreased from 77% to 42% by UF when the TMP increased from (1 to 3.6) bar. Total phenolic rejection decreased from 45% to 21% when the TMP rose from (1 to 2) bar and remained constant above this value. With the batch concentration mode at TMP = 2 bar and velocity 1 m·s–1 , the enzymatic treatment (5 U·mL–1 , 300 min, T = 20 °C) of pomegranate juice provided the highest permeate flux, a decrease in total phenolics of 50% and an increased clarity of 30%. Fouling of the UF membrane during pomegranate juice processing is mainly due to the retention of polyphenols and/or proteins; thus, several blocking mechanisms were studied, using a recently developed membrane-fouling model. Analysis revealed that the membrane separation process was controlled by the gel layer mechanism of raw pomegranate juice and complete pore blocking mechanism with enzymatic pre-treatment.

Effect of processing parameters on the microfiltration fouling during the clarification of pomegranate juice.

The pomegranate juice with high nutritional value has turbid appearance that makes it difficult to preserve and concentrate. Microfiltration is useful process which can clarify it. One of the most important problems in this process is fouling phenomenon which affected by several parameters. The effects of fluid velocity, transmembrane pressure, membrane type and its pore size on membrane fouling were studied. The results showed that the membrane fouling increased with increase in the fluid velocity and transmembrane pressure. Also, more hydrophilic property and pore size resulted more membrane fouling due to greater flux which move more particles to membrane surface. Scanning electron microscopy (SEM) images support these results. Keywords: Clarification, Fouling, Membrane, Pomegranate juice

Clarification of pomegranate juice by microfiltration with PVDF membranes

Microfiltration was used to clarify pomegranate juice using two polyvinylidene fluoride membranes with pore sizes of 0.22 and 0.45 μm. Changes were studied in the chemical properties of the juice after passing through each membrane. Characteristics such as turbidity changed for both membranes (more than 95%). The permeate flux decreased over time as a result of membrane fouling. The degree of decline in the membrane with pore size of 0.22 μm was greater than another one. In both membranes, fouling resistance increased over time from 5 × 10 9 m 2/kg to 4.43 × 10 10 m 2/kg for 0.22 μm and to 1.29 × 10 10 m 2/kg for 0.45 μm after 45 min. This increase had a sharp slope in the first stages of the testing. Fouling index changes over time showed similar behavior. Scanning electron microscopy images showed that the cake layer had the greatest impact on membrane fouling after processing by preventing turbid components from entering pores.

Study on the development of pomegranate juice processing technology: clarification of pomegranate juice.

The effects of clarification agents and methods on pomegranate juice quality were studied. Fruits were pressed as whole, and extracted juice was clarified with gelatin, polyvinylypolypyrrolidone (PVPP) and natural sedimentation. In order to determine the effects of these clarifying techniques on product quality, pH, total phenolic substances (TPS), anthocyanin, turbidity, and total colour density tests were applied to each sample. In clarification, the main purpose was to reduce the amount of phenolic substances. Phenolic substances were controlled in each clarification method. The most effective method was the application of 1 g/L gelatine for clarification. Sensory evaluation also applied for clarified juices and gelatin application was selected by panelists to be superior.